jackson: 1000 papers, Hirsch index 23, Hirsch ratio 0.023.
adsauthor "Jackson, B." abstract sloppy
Title: CoRoT-7b: Super-Earth or Super-Io?
Authors: Barnes, Rory; Raymond, Sean N.; Greenberg, Richard;
Jackson, Brian; Kaib, Nathan A.
Affiliation: AA(Department of Astronomy, University of
Washington, Seattle, WA 98195-1580, USA; Virtual
Planetary Laboratory. ), AB(Center for Astrophysics
and Space Astronomy, University of Colorado, UCB
389, Boulder, CO 80309-0389, USA; Virtual Planetary
Laboratory. ), AC(Lunar and Planetary Laboratory,
University of Arizona, Tucson, AZ 85721, USA ),
AD(Planetary Systems Laboratory, Goddard Space
Flight Center, Code 693, Greenbelt, MD 20771, USA;
NASA Postdoctoral Program Fellow.), AE(Department of
Astronomy, University of Washington, Seattle, WA
98195-1580, USA )
Publication: The Astrophysical Journal Letters, Volume 709, Issue
2, pp. L95-L98 (2010).
Publication Date: 02/2010
Origin: IOP
ApJ Keywords: celestial mechanics, planets and satellites:
individual: CoRoT-7b
DOI: 10.1088/2041-8205/709/2/L95
Bibliographic Code: 2010ApJ...709L..95B
Abstract
CoRoT-7b, a planet about 70% larger than the Earth orbiting a Sun-like
star, is the first-discovered rocky exoplanet, and hence has been dubbed
a "super-Earth." Some initial studies suggested that since the planet is
so close to its host star, it receives enough insolation to partially
melt its surface. However, these past studies failed to take into
consideration the role that tides may play in this system. Even if the
planet's eccentricity has always been zero, we show that tidal decay of
the semimajor axis could have been large enough that the planet formed
on a wider orbit which received less insolation. Moreover, CoRoT-7b
could be tidally heated at a rate that dominates its geophysics and
drives extreme volcanism. In this case, CoRoT-7b is a "super-Io" that,
like Jupiter's volcanic moon, is dominated by volcanism and rapid
resurfacing. Such heating could occur with an eccentricity of just
10--5. This small value could be driven by CoRoT-7c if
its own eccentricity is larger than ~10--4. CoRoT-7b may
be the first of a class of planetary super-Ios likely to be revealed by
the CoRoT and Kepler spacecraft.
Title: Phase change memory technology
Authors: Burr, Geoffrey W.; Breitwisch, Matthew J.;
Franceschini, Michele; Garetto, Davide;
Gopalakrishnan, Kailash; Jackson, Bryan;
Kurdi, Bulent; Lam, Chung; Lastras, Luis A.;
Padilla, Alvaro; Rajendran, Bipin; Raoux, Simone;
Shenoy, Rohit S.
Publication: eprint arXiv:1001.1164
Publication Date: 01/2010
Origin: ARXIV
Keywords: Condensed Matter - Materials Science
Comment: Review article
Bibliographic Code: 2010arXiv1001.1164B
Abstract
We survey the current state of phase change memory (PCM), a non-volatile
solid-state memory technology built around the large electrical contrast
between the highly-resistive amorphous and highly-conductive crystalline
states in so-called phase change materials. PCM technology has made
rapid progress in a short time, having passed older technologies in
terms of both sophisticated demonstrations of scaling to small device
dimensions, as well as integrated large-array demonstrators with
impressive retention, endurance, performance and yield characteristics.
We introduce the physics behind PCM technology, assess how its
characteristics match up with various potential applications across the
memory-storage hierarchy, and discuss its strengths including
scalability and rapid switching speed. We then address challenges for
the technology, including the design of PCM cells for low RESET current,
the need to control device-to-device variability, and undesirable
changes in the phase change material that can be induced by the
fabrication procedure. We then turn to issues related to operation of
PCM devices, including retention, device-to-device thermal crosstalk,
endurance, and bias-polarity effects. Several factors that can be
expected to enhance PCM in the future are addressed, including
Multi-Level Cell technology for PCM (which offers higher density through
the use of intermediate resistance states), the role of coding, and
possible routes to an ultra-high density PCM technology.
Title: Tidal Evolution of Hot Jupiter Planets
Authors: Miller, Neil; Fortney, J.; Jackson, B.
Affiliation: AA(UC Santa Cruz), AB(UC Santa Cruz), AC(NASA
Goddard Space Flight Center)
Publication: American Astronomical Society, AAS Meeting \#215,
\#349.06
Publication Date: 01/2010
Origin: AAS
Abstract Copyright: (c) 2010: American Astronomical Society
Bibliographic Code: 2010AAS...21534906M
Abstract
The observed transit radii of many hot Jupiter exoplanets have been
found to be unexpectedly large. Past studies proposed that tidal heating
of hot Jupiter during circularization of their planet's orbit might warm
the planet's interior, enlarging the radius, but for many inflated
planets, estimates of current heating rates are insufficient. However,
tidal heating rates for hot Jupiters may vary by orders of magnitude as
their orbits evolve. To study the effects of such variable tidal
heating, we applied a model that couples tidal and thermal evolution of
hot Jupiters. We find the the inflation of a planet's radius may persist
even after the heating rate becomes small, but this inflated state
without heating is transient and often last a few hundred million years.
Thus tidal heating via circularization of the planet's orbit may not be
a sufficient explanation for all unexpectedly large radius planets.
Although inflation by tidal heating may be short-lived, in some cases,
planets may over-flow their Roche lobes and undergo significant mass
loss. Evidence for such mass loss may be apparent in the distribution of
orbital and physical properties of observed planets.
Title: Is CoRoT-7 B the Remnant Core of an Evaporated Gas
Giant?
Authors: Jackson, Brian; Barnes, R.; Raymond, S. N.;
Fortney, J.; Greenberg, R.
Affiliation: AA(Goddard Space Flight Center), AB(Virtual Planet
Laboratory, University of Washington), AC(LAB:
Laboratoire d'Astrophysique de Bordeaux (CNRS,
Université Bordeaux 1) - BP 89 - F-33271, France),
AD(University of California Santa Cruz), AE(Lunar
and Planetary Laboratory, University of Arizona)
Publication: American Astronomical Society, AAS Meeting \#215,
\#339.05
Publication Date: 01/2010
Origin: AAS
Abstract Copyright: (c) 2010: American Astronomical Society
Bibliographic Code: 2010AAS...21533905J
Abstract
The recently discovered planet CoRoT-7 b has a density (5.7 g/cc)
consistent with a rocky composition (Leger et al. 2009; Queloz et al.
2009). However, CoRoT-7 b's semi-major axis (0.0172 AU) suggests the
planet has a history unlike the planets in our solar system. The strong
stellar insolation received by CoRoT-7 b can quickly drive off an
atmosphere and may have evaporated a few Earth masses of rocky material
during the planet's lifetime. Such rapid mass loss even suggests that
CoRoT-7 b may be the remnant core of a hot Jupiter whose gaseous
envelope was completely evaporated. Also important are tides, which have
drawn the planet in from a more distant, and possibly eccentric, orbit.
As the planet neared its host star, the rate of mass loss probably
increased dramatically, but mass loss slows tidal migration, resulting
in a complex interplay between tides and mass loss. We combine tidal
evolution and mass loss models to constrain the range of original orbits
and masses of CoRoT-7 b and find, indeed, that CoRoT-7 b may once have
been a gas giant planet. We discuss the plausible evolutionary pathways
that allow CoRoT-7 b to have begun life as a gas giant. Our results
suggest that similar processes may have influenced many other close-in
exoplanets as well. Studying the coupled processes of mass loss and
tidal migration may thus be crucial to unraveling the origins of the
hundreds of hot super-Earths that may soon be discovered by the Kepler
and CoRoT missions.
Title: CoRoT-7 b: Super-Earth or Super-Io?
Authors: Barnes, Rory; Raymond, S. N.; Greenberg, R.;
Jackson, B.; Kaib, N. A.
Affiliation: AA(University of Washington), AB(Laboratoire
d'Astrophysique de Bordeaux, France), AC(University
of Arizona), AD(Goddard Space Flight Center),
AE(University of Washington)
Publication: American Astronomical Society, AAS Meeting \#215,
\#339.04
Publication Date: 01/2010
Origin: AAS
Abstract Copyright: (c) 2010: American Astronomical Society
Bibliographic Code: 2010AAS...21533904B
Abstract
CoRoT-7 b, a planet about 70% larger than the Earth orbiting a Sun-like
star, is the first-discovered rocky exoplanet, and hence has been dubbed
a "super-Earth". Initial studies indicate that the planet receives
enough insolation to partially melt its surface. However, tides also
contribute significantly to the heat budget in several ways. Even if
there has never been direct tidal heating (e.g. if the planet's
eccentricity has always been zero), orbital decay by tides may have very
recently placed the planet in an orbit in which its insolation could
melt silicates. On the other hand, CoRoT-7 b could be tidally heated at
a rate that dominates its geophysics and drives extreme volcanism,
making it a "super-Io" similar to Jupiter's volcanic moon. Such heating
could occur with an eccentricity of just 10-5. Although this
value is very small, the tidal damping of eccentricity is extreme due to
the very small orbit. We have considered various mechanisms for
maintaining a non-zero eccentricity, but only perturbations from CoRoT-7
c can raise b's eccentricity large enough to induce Io-like heating, and
only if its eccentricity is of order 10-4. Such a value is
plausible, though below current detection thresholds. Nonetheless,
CoRoT-7 b may be the first of a class of planetary super-Ios likely to
be revealed by the CoRoT and Kepler spacecraft.
Title: Methane Dissociation on Ni(111): A New Understanding
of the Lattice Effect
Authors: Tiwari, Ashwani Kumar; Nave, Sven; Jackson, Bret
Affiliation: AA(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA),
AB(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA),
AC(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA)
Publication: Physical Review Letters, vol. 103, Issue 25, id.
253201
Publication Date: 12/2009
Origin: APS
PACS Keywords: Scattering of atoms and molecules
Abstract Copyright: (c) 2009: The American Physical Society
DOI: 10.1103/PhysRevLett.103.253201
Bibliographic Code: 2009PhRvL.103y3201T
Abstract
The nature of the lattice motion during the dissociation of methane on
Ni(111) is analyzed in great detail, and various models for including
lattice effects are explored. It is shown that the thermal vibrations of
the lattice strongly modify the reactivity, but that the lattice motion
is relatively unperturbed by the incident molecule during the collision,
in contrast with several earlier predictions. Based on these studies we
propose a new model to describe the effects of lattice motion, which
agrees well with exact quantum calculations.
Title: Simulating PM concentration during a winter episode
in a subtropical valley: Sensitivity simulations and
evaluation methods
Authors: Livingstone, P. L.; Magliano, K.; Gürer, K.;
Allen, P. D.; Zhang, K. M.; Ying, Q.; Jackson, B. S.;
Kaduwela, A.; Kleeman, M.; Woodhouse, L. F.;
Turkiewicz, K.; Horowitz, L. W.; Scott, K.;
Johnson, D.; Taylor, C.; O'Brien, G.; DaMassa, J.;
Croes, B. E.; Binkowski, F.; Byun, D.
Publication: Atmospheric Environment, v. 43, iss. 38, p.
5971-5977.
Publication Date: 12/2009
Origin: ELSEVIER
Bibliographic Code: 2009AtmEn..43.5971L
Abstract
Not Available
Title: Tidal Constraints on Planetary Habitability
Authors: Barnes, Rory; Jackson, Brian; Greenberg, Richard;
Raymond, Sean N.; Heller, Rene
Publication: eprint arXiv:0912.2095
Publication Date: 12/2009
Origin: ARXIV
Keywords: Astrophysics - Earth and Planetary Astrophysics
Comment: 6 pages, 3 figures. Proceedings submitted to
"Pathways Towards Habitable Planets" Symposium
(eds.: D. Gelino, V. Coude du Foresto, I. Ribas)
Bibliographic Code: 2009arXiv0912.2095B
Abstract
We review how tides may impact the habitability of terrestrial-like
planets. If such planets form around low-mass stars, then planets in the
circumstellar habitable zone will be close enough to their host stars to
experience strong tidal forces. We discuss 1) decay of semi-major axis,
2) circularization of eccentric orbits, 3) evolution toward zero
obliquity, 4) fixed rotation rates (not necessarily synchronous), and 5)
internal heating. We briefly describe these effects using the example of
a 0.25 solar mass star with a 10 Earth-mass companion. We suggest that
the concept of a habitable zone should be modified to include the
effects of tides.
Title: 3-D reconstructions of the early-November 2004 CDAW
geomagnetic storms: analysis of Ooty IPS speed and
density data
Authors: Bisi, M. M.; Jackson, B. V.; Clover, J. M.;
Manoharan, P. K.; Tokumaru, M.; Hick, P. P.;
Buffington, A.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, USA
Space Sciences, University of California, San Diego,
9500 Gilman Drive \#0424, La Jolla, CA 92093-0424,
USA), AC(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, USA), AD(Radio
Astronomy Centre, National Centre for Radio
Astrophysics, Tata Institute of Fundamental
Research, Udhagamandalam (Ooty), 643 001, India),
AE(Solar-Terrestrial Environment Laboratory
(STELab), Nagoya University, Furo-cho, Chikusa-ku,
Nagoya 464-8601, Japan), AF(Center for Astrophysics
and Space Sciences, University of California, San
Diego, 9500 Gilman Drive \#0424, La Jolla, CA
92093-0424, USA; San Diego Supercomputer Center,
University of California, San Diego, 9500 Gilman
Drive \#0505, La Jolla, CA 92093-0505, USA),
AG(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, USA)
Publication: Annales Geophysicae, Volume 27, Issue 12, 2009,
pp.4479-4489
Publication Date: 12/2009
Origin: COPERNICUS
Bibliographic Code: 2009AnGeo..27.4479B
Abstract
Interplanetary scintillation (IPS) remote-sensing observations provide a
view of the solar wind covering a wide range of heliographic latitudes
and heliocentric distances from the Sun between ~0.1 AU and 3.0 AU. Such
observations are used to study the development of solar coronal
transients and the solar wind while propagating out through
interplanetary space. They can also be used to measure the
inner-heliospheric response to the passage of coronal mass ejections
(CMEs) and co-rotating heliospheric structures. IPS observations can, in
general, provide a speed estimate of the heliospheric material crossing
the observing line of site; some radio antennas/arrays can also provide
a radio scintillation level. We use a three-dimensional (3-D)
reconstruction technique which obtains perspective views from
outward-flowing solar wind and co-rotating structure as observed from
Earth by iteratively fitting a kinematic solar wind model to these data.
Using this 3-D modelling technique, we are able to reconstruct the
velocity and density of CMEs as they travel through interplanetary
space. For the time-dependent model used here with IPS data taken from
the Ootacamund (Ooty) Radio Telescope (ORT) in India, the digital
resolution of the tomography is 10° by 10° in both latitude and
longitude with a half-day time cadence. Typically however, the
resolutions range from 10° to 20° in latitude and longitude,
with a half- to one-day time cadence for IPS data dependant upon how
much data are used as input to the tomography. We compare reconstructed
structures during early-November 2004 with in-situ measurements from the
Wind spacecraft orbiting the Sun-Earth L1-Point to validate
the 3-D tomographic reconstruction results and comment on how these
improve upon prior reconstructions.
Title: SMEI direct, 3-D-reconstruction sky maps, and
volumetric analyses, and their comparison with SOHO
and STEREO observations
Authors: Jackson, B. V.; Hick, P. P.; Buffington, A.;
Bisi, M. M.; Clover, J. M.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, 92093-0424 CA, USA
and Space Sciences, University of California, San
Diego, 9500 Gilman Drive \#0424, La Jolla, 92093-0424
CA, USA), AC(Center for Astrophysics and Space
Sciences, University of California, San Diego, 9500
Gilman Drive \#0424, La Jolla, 92093-0424 CA, USA),
AD(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, 92093-0424 CA, USA),
AE(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, 92093-0424 CA, USA)
Publication: Annales Geophysicae, Volume 27, Issue 11, 2009,
pp.4097-4104
Publication Date: 11/2009
Origin: COPERNICUS
Bibliographic Code: 2009AnGeo..27.4097J
Abstract
In this paper we present the results of the analysis of the late January
2007 Coronal Mass Ejection (CME) events recorded by the Solar Mass
Ejection Imager (SMEI), the Solar TErrestrial RElations Observatory
(STEREO), and the SOlar and Heliospheric Observatory (SOHO) spacecraft.
This period occurs when the two STEREO spacecraft views are from close
to Earth, and thus the views from both SMEI and the STEREO outer
Heliospheric Imagers (HI-2s) coincide. Three-dimensional (3-D) analyses
derived from SMEI data show many CMEs that have also been studied by
others using short-term image subtractions (image-differencing
techniques). During this interval we map several CME structures that are
observed in both SMEI and the STEREO-A HI instruments. SMEI brightness
analyses provided by short-term image subtractions ("difference images")
and, alternatively, subtractions of a mean-brightness fit over a
long-time duration, both show the extents of the CMEs travelling outward
above the East limb that erupted from the Sun on 24 and 25 January 2007.
The SMEI 3-D-reconstructions not only enhance distinct features within
the CME events, but also reconcile difference-imaging results with those
where a long-term base has been removed. In the January 2007 example the
structure as mapped by CME difference images traces the sharp intensity
gradients at the front of the CMEs; generally brighter ejected material
follows behind the location of the CME front, but shows poorly in these
because of its larger angular extent. Using the long-duration background
removal enables SMEI's 3-D analysis to determine a mass for this CME
sequence North of the ecliptic.
Title: Linear State Feedback Stabilization on Time Scales
Authors: Jackson, Billy J.; Davis, John M.; Gravagne, Ian A.;
Marks, Robert J., II
Publication: eprint arXiv:0910.3034
Publication Date: 10/2009
Origin: ARXIV
Keywords: Mathematics - Optimization and Control, 93B52, 93D15
Comment: 15 pages
Bibliographic Code: 2009arXiv0910.3034J
Abstract
For a general class of dynamical systems (of which the canonical
continuous and uniform discrete versions are but special cases), we
prove that there is a state feedback gain such that the resulting
closed-loop system is uniformly exponentially stable with a prescribed
rate. The methods here generalize and extend Gramian-based linear state
feedback control to much more general time domains, e.g. nonuniform
discrete or a combination of continuous and discrete time. In
conclusion, we discuss an experimental implementation of this theory.
Title: Measurements of the Gegenschein brightness from the
Solar Mass Ejection Imager (SMEI)
Authors: Buffington, Andrew; Bisi, Mario M.; Clover, John M.;
Hick, P. Paul; Jackson, Bernard V.;
Kuchar, Thomas A.; Price, Stephan D.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive, MS 0424, La Jolla, CA 92093-0424, USA),
AB(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive, MS 0424, La Jolla, CA 92093-0424, USA),
AC(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive, MS 0424, La Jolla, CA 92093-0424, USA),
AD(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive, MS 0424, La Jolla, CA 92093-0424, USA),
AE(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive, MS 0424, La Jolla, CA 92093-0424, USA),
AF(Institute for Scientific Research, Boston
College, Chestnut Hill, MA 02147, USA), AG(Air Force
Research Laboratory/Space Vehicles Directorate
(AFRL/RVB), Hanscom AFB, MA 01731-3010, USA)
Publication: Icarus, Volume 203, Issue 1, p. 124-133.
Publication Date: 09/2009
Origin: ELSEVIER
DOI: 10.1016/j.icarus.2009.04.007
Bibliographic Code: 2009Icar..203..124B
Abstract
The Gegenschein is viewed by the Solar Mass Ejection Imager (SMEI),
which has provided near-full-sky broadband visible-light photometric
maps for over 5 years. These have an angular resolution of about
0.5° and differential photometric stability of about 1% throughout
this time. When individual bright stars are removed from the maps and an
empirical sidereal background subtracted, the residue is dominated by
the zodiacal light. The unprecedented sky coverage and duration of these
measurements enables a definitive characterization of the Gegenschein.
This article describes the analysis method for these data, presents a
movie with time of the Gegenschein brightness distribution, determines
empirical formulae describing its average shape, and discusses its
variation with time. These measurements unambiguously confirm previous
reports that the Gegenschein surface-brightness distribution has a
decided peak in the antisolar point, which rises above a broader
background.
Title: Effects of Secular, Resonant and Tidal Perturbations
on Planetary Habitability
Authors: Jackson, Brian; Barnes, R.; Raymond, S.;
Greenberg, R.
Affiliation: AA(Goddard Space Flight Center), AB(Virtual Planet
Laboratory, University of Washington), AC(Center for
Astrophysics, University of Colorado), AD(Lunar and
Planetary Laboratory, University of Arizona)
Publication: American Astronomical Society, DPS meeting \#41,
\#5.05
Publication Date: 09/2009
Origin: AAS
Bibliographic Code: 2009DPS....41.0505J
Abstract
As observational techniques improve and new planet-finding missions come
online (such as Kepler), observers will soon find extra-solar planets
with compositions and masses similar to the terrestrial planets in our
solar system. The discovery of such planets represents a crucial step in
finding life outside our own solar system. However, the suitability of
these planets for life depends on many factors, and the planets'
semi-major axes and eccentricities play an important role. If a
terrestrial-scale planet is a member of a multi-planet system, secular
and resonant perturbations from the other planets can cause the planet's
orbital elements to oscillate over tens of thousands of years. For
planets with orbits very close to their host stars, tides may also be
important, and the interplay between tidal, resonant and secular
perturbations may produce complex effects. Dissipation of tidal energy
within a terrestrial-scale planet may help drive important geophysical
processes (e.g. volcanism or tectonic activity), and oscillations in
orbital elements resulting from secular or resonant perturbations may
cause the tidal heating to oscillate as well. We present models of the
orbital evolution of a suite of hypothetical terrestrial-scale planets
and discuss possible effects on habitability, geophysics and
atmospheres. For example, oscillations in a planet's orbital
eccentricity may induce climatic variations similar to the Milankovitch
cycle on the Earth, perhaps causing planets to periodically ice over.
Title: Inflating and Deflating Hot Jupiters: Coupled Tidal
and Thermal Evolution of Known Transiting Planets
Authors: Miller, N.; Fortney, J. J.; Jackson, B.
Affiliation: AA(Department of Astronomy and Astrophysics,
University of California, Santa Cruz, CA 95064, USA
and Astrophysics, University of California, Santa
AC(Lunar and Planetary Laboratory, University of
Arizona, Tucson, AZ 85721, USA
Publication: The Astrophysical Journal, Volume 702, Issue 2, pp.
1413-1427 (2009).
Publication Date: 09/2009
Origin: IOP
ApJ Keywords: planetary systems, planets and satellites: general
DOI: 10.1088/0004-637X/702/2/1413
Bibliographic Code: 2009ApJ...702.1413M
Abstract
We examine the radius evolution of close in giant planets with a planet
evolution model that couples the orbital-tidal and thermal evolution.
For 45 transiting systems, we compute a large grid of
cooling/contraction paths forward in time, starting from a large phase
space of initial semimajor axes and eccentricities. Given observational
constraints at the current time for a given planet (semimajor axis,
eccentricity, and system age), we find possible evolutionary paths that
match these constraints, and compare the calculated radii to
observations. We find that tidal evolution has two effects. First,
planets start their evolution at larger semimajor axis, allowing them to
contract more efficiently at earlier times. Second, tidal heating can
significantly inflate the radius when the orbit is being circularized,
but this effect on the radius is short-lived thereafter. Often
circularization of the orbit is proceeded by a long period while the
semimajor axis slowly decreases. Some systems with previously
unexplained large radii that we can reproduce with our coupled model are
HAT-P-7, HAT-P-9, WASP-10, and XO-4. This increases the number of
planets for which we can match the radius from 24 (of 45) to as many as
35 for our standard case, but for some of these systems we are required
to be viewing them at a special time around the era of current radius
inflation. This is a concern for the viability of tidal inflation as a
general mechanism to explain most inflated radii. Also, large initial
eccentricities would have to be common. We also investigate the
evolution of models that have a floor on the eccentricity, as may be due
to a perturber. In this scenario, we match the extremely large radius of
WASP-12b. This work may cast some doubt on our ability to accurately
determine the interior heavy element enrichment of normal, noninflated
close in planets, because of our dearth of knowledge about these
planets' previous orbital-tidal histories. Finally, we find that the end
state of most close in planetary systems is disruption of the planet as
it moves ever closer to its parent star.
Title: Fabrication and test of a diamond-turned mirror
suitable for a spaceborne photometric heliospheric
imager
Authors: Buffington, Andrew; Bach, Kirk G.; Bach, Bernhard W.;
Bach, Erich K.; Bisi, Mario M.; Hick, P. Paul;
Jackson, Bernard V.; Klupar, Peter D.
Affiliation: AA(Ctr. for Astrophysics and Space Sciences, Univ.
of California, San Diego (USA)), AB(Bach Research
Corp. (USA)), AC(Bach Research Corp. (USA)), AD(Bach
Research Corp. (USA)), AE(Ctr. for Astrophysics and
Space Sciences, Univ. of California, San Diego
(USA)), AF(Ctr. for Astrophysics and Space Sciences,
Univ. of California, San Diego (USA) and San Diego
Supercomputer Ctr., Univ. of California, San Diego
(USA)), AG(Ctr. for Astrophysics and Space Sciences,
Univ. of California, San Diego (USA)), AH(NASA Ames
Research Ctr. (USA))
Publication: Solar Physics and Space Weather Instrumentation III.
Edited by Fineschi, Silvano; Fennelly, Judy A.
Proceedings of the SPIE, Volume 7438, pp.
74380O-74380O-12 (2009).
Publication Date: 08/2009
Origin: AIP
Abstract Copyright: (c) 2009: American Institute of Physics
DOI: 10.1117/12.825362
Bibliographic Code: 2009SPIE.7438E..17B
Abstract
We have fabricated a diamond-turned low-mass version of a toroidal
mirror which is a key element for a spaceborne visible-light
heliospheric imager. This mirror's virtual image of roughly a hemisphere
of sky is viewed by a conventional photometric camera. The optical
system views close to the edge of an external protective baffle and does
not protrude from the protected volume. The sky-brightness dynamic range
and background-light rejection requires minimal wideangle scattering
from the mirror surface. We describe the manufacturing process for this
mirror, and present preliminary laboratory measurements of its
wide-angle scattering characteristics.
Title: Hybrid quintessential inflation
Authors: Bastero-Gil, Mar; Berera, Arjun; Jackson, Brendan M.;
Taylor, Andy
Affiliation: AA(Departamento de Física Teórica y del Cosmos,
Universidad de Granada, Granada-18071, Spain),
AB(School of Physics and Astronomy, University of
Edinburgh, Edinburgh EH9 3JZ, UK), AC(Institute for
Astronomy, School of Physics and Astronomy,
University of Edinburgh, Edinburgh EH9 3HJ, UK),
AD(Institute for Astronomy, School of Physics and
Astronomy, University of Edinburgh, Edinburgh EH9
3HJ, UK)
Publication: Physics Letters B, Volume 678, Issue 2, p. 157-163.
Publication Date: 07/2009
Origin: ELSEVIER
Keywords: 98.80.Cq, 95.36.+x
DOI: 10.1016/j.physletb.2009.06.025
Bibliographic Code: 2009PhLB..678..157B
Abstract
A model is presented in which a single scalar field is responsible for
both primordial inflation at early times and then dark energy at late
times. This field is coupled to a second scalar field which becomes
unstable and starts to oscillate after primordial inflation, thus
driving a reheating phase that can create a high post-inflation
temperature. This model easily avoids overproduction of gravity waves,
which is a problem in the original quintessential inflation model in
which reheating occurs via gravitational particle production.
Title: Tidal Limits to Planetary Habitability
Authors: Barnes, Rory; Jackson, Brian; Greenberg, Richard;
Raymond, Sean N.
Affiliation: AA(Department of Astronomy, University of
Washington, Seattle, WA 98195-1580, USA; Virtual
Planetary Laboratory, USA ), AB(Lunar and Planetary
Laboratory, University of Arizona, Tucson, AZ 85721,
USA ), AC(Lunar and Planetary Laboratory, University
of Arizona, Tucson, AZ 85721, USA ), AD(Virtual
Planetary Laboratory, USA; Center for Astrophysics
and Space Astronomy, University of Colorado, UCB
389, Boulder, CO 80309-0389, USA)
Publication: The Astrophysical Journal Letters, Volume 700, Issue
1, pp. L30-L33 (2009).
Publication Date: 07/2009
Origin: IOP
ApJ Keywords: astrobiology, planetary systems, stars: individual:
GJ 581, stars: low-mass, brown dwarfs
DOI: 10.1088/0004-637X/700/1/L30
Bibliographic Code: 2009ApJ...700L..30B
Abstract
The habitable zones (HZs) of main-sequence stars have traditionally been
defined as the range of orbits that intercept the appropriate amount of
stellar flux to permit surface water on a planet. Terrestrial exoplanets
discovered to orbit M stars in these zones, which are close-in due to
decreased stellar luminosity, may also undergo significant tidal
heating. Tidal heating may span a wide range for terrestrial exoplanets
and may significantly affect conditions near the surface. For example,
if heating rates on an exoplanet are near or greater than that on Io
(where tides drive volcanism that resurfaces the planet at least every 1
Myr) and produce similar surface conditions, then the development of
life seems unlikely. On the other hand, if the tidal heating rate is
less than the minimum to initiate plate tectonics, then CO2
may not be recycled through subduction, leading to a runaway greenhouse
that sterilizes the planet. These two cases represent potential
boundaries to habitability and are presented along with the range of the
traditional HZ for main-sequence, low-mass stars. We propose a revised
HZ that incorporates both stellar insolation and tidal heating. We apply
these criteria to GJ 581 d and find that it is in the traditional HZ,
but its tidal heating alone may be insufficient for plate tectonics.
Title: Observational Evidence for Tidal Destruction of
Exoplanets
Authors: Jackson, Brian; Barnes, Rory; Greenberg, Richard
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona, 1629 E University Blvd, Tucson AZ
85721-0092, USA ), AB(Lunar and Planetary
Laboratory, University of Arizona, 1629 E University
Blvd, Tucson AZ 85721-0092, USA; Astronomy
Department, University of Washington, Box 351580,
Seattle WA, USA; Virtual Planetary Laboratory),
AC(Lunar and Planetary Laboratory, University of
Arizona, 1629 E University Blvd, Tucson AZ
85721-0092, USA )
Publication: The Astrophysical Journal, Volume 698, Issue 2, pp.
1357-1366 (2009).
Publication Date: 06/2009
Origin: IOP
ApJ Keywords: planetary systems: formation, planetary systems:
protoplanetary disks
DOI: 10.1088/0004-637X/698/2/1357
Bibliographic Code: 2009ApJ...698.1357J
Abstract
The distribution of the orbits of close-in exoplanets shows evidence for
ongoing removal and destruction by tides. Tides raised on a planet's
host star cause the planet's orbit to decay, even after the orbital
eccentricity has dropped to zero. Comparison of the observed orbital
distribution and predictions of tidal theory shows good qualitative
agreement, suggesting tidal destruction of close-in exoplanets is
common. The process can explain the observed cutoff in small semimajor
axis values, the clustering of orbital periods near three days, and the
relative youth of transiting planets. Contrary to previous
considerations, a mechanism to stop the inward migration of close-in
planets at their current orbits is not necessarily required. Planets
nearing tidal destruction may be found with extremely small semimajor
axes, possibly already stripped of any gaseous envelope. The recently
discovered CoroT-7 b may be an example of such a planet and will
probably be destroyed by tides within the next few Gyrs. Also, where one
or more planets have already been accreted, a star may exhibit an
unusual composition and/or spin rate.
Title: Studying geoeffective interplanetary coronal mass
ejections between the Sun and Earth: Space weather
implications of Solar Mass Ejection Imager
observations
Authors: Webb, D. F.; Howard, T. A.; Fry, C. D.;
Kuchar, T. A.; Mizuno, D. R.; Johnston, J. C.;
Jackson, B. V.
Affiliation: AA(Space Vehicles Directorate, Air Force Research
Laboratory, Hanscom Air Force Base, Massachusetts,
USA); AB(Air Force Research Laboratory, National
Solar Observatory, Sunspot, New Mexico, USA);
AC(Exploration Physics International, Inc.,
Huntsville, Alabama, USA); AD(Space Vehicles
Directorate, Air Force Research Laboratory, Hanscom
Air Force Base, Massachusetts, USA); AE(Space
Vehicles Directorate, Air Force Research Laboratory,
Hanscom Air Force Base, Massachusetts, USA);
AF(Space Vehicles Directorate, Air Force Research
Laboratory, Hanscom Air Force Base, Massachusetts,
USA); AG(Center for Astrophysics and Space Science,
University of California, San Diego, La Jolla,
California, USA)
Publication: Space Weather, Volume 7, Issue 5, CiteID S05002
Publication Date: 05/2009
Origin: AGU
AGU Keywords: Interplanetary Physics: Coronal mass ejections
(7513), Interplanetary Physics: Ejecta, driver
gases, and magnetic clouds, Interplanetary Physics:
Solar wind plasma, Space Weather: Magnetic storms
(2788)
Abstract Copyright: (c) 2009: American Geophysical Union
DOI: 10.1029/2008SW000409
Bibliographic Code: 2009SpWea...705002W
Abstract
Interplanetary coronal mass ejections (ICMEs) are the primary cause of
severe space weather at Earth because they drive shocks and trigger
geomagnetic storms that can damage spacecraft and ground-based systems.
The Solar Mass Ejection Imager (SMEI) is a U. S. Air Force experiment
with the ability to track ICMEs in white light from near the Sun to
Earth and beyond, thus providing an extended observational range for
forecasting storms. We summarize several studies of SMEI's detection and
tracking capability, especially of the ICMEs associated with the intense
(peak Dst <= -100 nT) geomagnetic storms that were the focus of
the NASA Living With a Star Geostorm Coordinated Data Analysis Workshop.
We describe the SMEI observations and analyses for the 18 intense storms
observed from May 2003--2007 with adequate SMEI coverage and
identified solar and interplanetary source regions. SMEI observed the
associated ICMEs for 89% of these intense storms. For each event we
extracted the time differences between these sets of times at 1 AU for
shock arrival time, predicted ICME arrival time, onset of high-altitude
aurora observed by SMEI, and storm onset. The mean intervals between
successive pairs of these data were found to each be ~4 hours. On
average, SMEI first detected the geoeffective ICME about 1 day in
advance, yielding a prediction lead time of ~18 hours. Finally, the
RMS values for the ICME-shock and storm-ICME time differences were
determined, and provide at least a 1-hour improvement compared to
similar observational and model-dependent studies.
Title: Three-Dimensional Reconstructions of the Solar Wind:
During Solar Minimum Conditions
Authors: Bisi, Mario; Jackson, B. V.; Hick, P. P. L.;
Clover, J. M.; Tokumaru, M.; Fujiki, K.;
Fallows, R. A.; Breen, A. R.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego), AB(Center for
Astrophysics and Space Sciences, University of
California, San Diego), AC(Center for Astrophysics
and Space Sciences, University of California, San
Diego), AD(Center for Astrophysics and Space
Sciences, University of California, San Diego),
AE(Solar-Terrestrial Environment Laboratory
(STELab), Nagoya University, Japan),
AF(Solar-Terrestrial Environment Laboratory
(STELab), Nagoya University, Japan), AG(Institute of
Mathematical and Physical Sciences, Aberystwyth
University, United Kingdom), AH(Institute of
Mathematical and Physical Sciences, Aberystwyth
University, United Kingdom)
Publication: American Astronomical Society, SPD meeting \#40,
\#32.03; Bulletin of the American Astronomical
Society, Vol. 41, p.866
Publication Date: 05/2009
Origin: AAS
Bibliographic Code: 2009SPD....40.3203B
Abstract
Interplanetary scintillation (IPS) observations provide information
about a vast region of the inner heliosphere. We use Solar-Terrestrial
Environment Laboratory (STELab) IPS velocity and g-level observations as
well as IPS velocity observations from the European Incoherent SCATter
(EISCAT) and EISCAT Svalbard Radar (ESR), with our three-dimensional
(3D) reconstruction model to determine velocities and densities of the
inner heliosphere. We present these observations using various forms of
imaging from our time-dependent model that can measure changes with
durations of less than a day and compare these with various spacecraft
in situ measurements. We concentrate on the current solar-minimum period
showing relatively-stable large-scale solar-wind structure during this
time in relation to transients that are also sometimes present. Data
primarily covers the 2007-2009 International Heliophysical Year (IHY)
which includes the Whole Heliosphere Interval (CR2068).
Title: CMEs In The Heliosphere Observed With Combined
Imaging And In-situ Data From LASCO, Stereo And SMEI
Authors: Webb, David F.; Biesecker, D.; Howard, T. A.;
Luhmann, J. G.; Li, Y.; Galvin, A.; Howard, R. A.;
Jackson, B. V.
Affiliation: AA(Boston College), AB(NOAA Space Weather Prediction
Center), AC(Air Force Research Laboratory, National
Solar Observatory,), AD(Space Sciences Laboratory,
University of California- Berkeley), AE(Space
Sciences Laboratory, University of California-
Berkeley), AF(University of New Hampshire), AG(Naval
Research Laboratory, Space Sciences Div.,), AH(CASS,
University of California, San Diego)
Publication: American Astronomical Society, SPD meeting \#40,
\#21.02; Bulletin of the American Astronomical
Society, Vol. 41, p.855
Publication Date: 05/2009
Origin: AAS
Bibliographic Code: 2009SPD....40.2102W
Abstract
Despite being in solar activity minimum, there have been a number of
events in which a CME observed at the Sun by one or both STEREO
spacecraft has passed over one of them (or the Earth) as detected from
in-situ data. These form a special class of space weather-type events
that can provide information on the characteristics of the geometry,
propagation and internal structure of CMEs. Important to this study are
the remote imaging observations from the SECCHI Heliospheric Imagers
(HIs) and, occasionally, also from the Solar Mass Ejection Imager (SMEI)
in Earth orbit. HI and SMEI observations of ICMEs can provide
complementary information. I will review these types of events and
summarize their characteristics and what they tell us about CMEs.
Title: 3D-Reconstruction of Density Enhancements Behind
Interplanetary Shocks from Solar Mass Ejection
White-Light Observations
Authors: Jackson, Bernard V.; Hick, P. P. L.; Buffington, A.;
Bisi, M. M.; Clover, J. M.; Tokumaru, M.; Fujiki, K.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego), AB(Center for
Astrophysics and Space Sciences, University of
California, San Diego), AC(Center for Astrophysics
and Space Sciences, University of California, San
Diego), AD(Center for Astrophysics and Space
Sciences, University of California, San Diego),
AE(Center for Astrophysics and Space Sciences,
University of California, San Diego),
AF(Solar-Terrestrial Environment Laboratory, Nagoya
University, Japan), AG(Solar-Terrestrial Environment
Laboratory, Nagoya University, Japan)
Publication: American Astronomical Society, SPD meeting \#40,
\#21.01; Bulletin of the American Astronomical
Society, Vol. 41, p.854
Publication Date: 05/2009
Origin: AAS
Bibliographic Code: 2009SPD....40.2101J
Abstract
The Solar Mass Ejection Imager (SMEI) observes the increased brightness
from the density enhancements behind interplanetary shocks that are
observed in situ near the Earth. We use the University of California,
San Diego time-dependent three-dimensional-reconstruction technique to
map the extents of these density enhancements. As examples, we examine
the shock density enhancements associated with several well-known
coronal mass ejections including the 28 October 2003 (Halloween storm)
event. We compare these density enhancements with reconstructed velocity
observations from Solar-Terrestrial Environment Laboratory
interplanetary scintillation (IPS) observations when these are
available. Volumetric-differencing techniques available from the SMEI
analyses show that the outer portion of a larger increase in
heliospheric density is often what is observed in short-time image
brightness subtractions from these data.
Title: Study of CME Propagation in the Inner Heliosphere:
SOHO LASCO, SMEI and STEREO HI Observations of the
January 2007 Events
Authors: Webb, D. F.; Howard, T. A.; Fry, C. D.;
Kuchar, T. A.; Odstrcil, D.; Jackson, B. V.;
Bisi, M. M.; Harrison, R. A.; Morrill, J. S.;
Howard, R. A.; Johnston, J. C.
Affiliation: AA(Institute for Scientific Research, Boston
College; Air Force Research Laboratory, Space
Vehicles Directorate), AB(Air Force Research
Laboratory, National Solar Observatory),
AC(Exploration Physics International, Inc.),
AD(Institute for Scientific Research, Boston
College; Air Force Research Laboratory, Space
Vehicles Directorate), AE(Cooperative Institute for
Research in Environmental Sciences, University of
Colorado; Space Weather Prediction Center, National
Oceanic and Atmospheric Administration), AF(Center
for Astrophysics and Space Science, University of
California-San Diego), AG(Center for Astrophysics
and Space Science, University of California-San
Diego), AH(Space Physics Division, Space Science and
Technology Dept., Rutherford Appleton Laboratory),
AI(Space Science Division, Code 7663, Naval Research
Laboratory), AJ(Space Science Division, Code 7663,
Naval Research Laboratory), AK(Air Force Research
Laboratory, Space Vehicles Directorate)
Publication: Solar Physics, Volume 256, Issue 1-2, pp. 239-267
Publication Date: 05/2009
Origin: SPRINGER
Keywords: Coronal mass ejections, Corona, Interplanetary
plasma
DOI: 10.1007/s11207-009-9351-8
Bibliographic Code: 2009SoPh..256..239W
Abstract
We are investigating the geometric and kinematic characteristics of
interplanetary coronal mass ejections (ICMEs) using data obtained by the
LASCO coronagraphs, the Solar Mass Ejection Imager (SMEI), and the
SECCHI imaging experiments on the STEREO spacecraft. The early evolution
of CMEs can be tracked by the LASCO C2 and C3 and SECCHI COR1 and COR2
coronagraphs, and the HI and SMEI instruments can track their ICME
counterparts through the inner heliosphere. The HI fields of view (4
- 90°) overlap with the SMEI field of view (> 20° to
all sky) and, thus, both instrument sets can observe the same ICME. In
this paper we present results for ICMEs observed on 24 - 29
January 2007, when the STEREO spacecraft were still near Earth so that
both the SMEI and STEREO views of large ICMEs in the inner heliosphere
coincided. These results include measurements of the structural and
kinematic evolution of two ICMEs and comparisons with drive/drag
kinematic, 3D tomographic reconstruction, the HAFv2 kinematic, and the
ENLIL MHD models. We find it encouraging that the four model runs
generally were in agreement on both the kinematic evolution and
appearance of the events. Because it is essential to understand the
effects of projection across large distances, that are not generally
crucial for events observed closer to the Sun, we discuss our analysis
procedure in some detail.
Title: Low-Resolution STELab IPS 3D Reconstructions of the
Whole Heliosphere Interval and Comparison with
in-Ecliptic Solar Wind Measurements from STEREO and
Wind Instrumentation
Authors: Bisi, M. M.; Jackson, B. V.; Buffington, A.;
Clover, J. M.; Hick, P. P.; Tokumaru, M.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego), AB(Center for
Astrophysics and Space Sciences, University of
California, San Diego), AC(Center for Astrophysics
and Space Sciences, University of California, San
Diego), AD(Center for Astrophysics and Space
Sciences, University of California, San Diego),
AE(Center for Astrophysics and Space Sciences,
University of California, San Diego),
AF(Solar-Terrestrial Environment Laboratory, Nagoya
University)
Publication: Solar Physics, Volume 256, Issue 1-2, pp. 201-217
Publication Date: 05/2009
Origin: SPRINGER
DOI: 10.1007/s11207-009-9350-9
Bibliographic Code: 2009SoPh..256..201B
Abstract
We present initial 3D tomographic reconstructions of the inner
heliosphere during the Whole Heliosphere Interval (WHI) -
Carrington Rotation 2068 (CR2068) - using Solar-Terrestrial
Environment Laboratory (STELab) Interplanetary Scintillation (IPS)
observations. Such observations have been used for over a decade to
visualise and investigate the structure of the solar wind and to study
in detail its various features. These features include co-rotating
structures as well as transient structures moving out from the Sun. We
present global reconstructions of the structure of the inner heliosphere
during this time, and compare density and radial velocity with
multi-point in situ spacecraft measurements in the ecliptic; namely
STEREO and Wind data, as the interplanetary medium passes over the
spacecraft locations.
Title: Finite-temperature vortex dynamics in Bose-Einstein
condensates
Authors: Jackson, B.; Proukakis, N. P.; Barenghi, C. F.;
Zaremba, E.
Affiliation: AA(School of Mathematics and Statistics, Newcastle
University, Newcastle upon Tyne NE1 7RU, United
Kingdom), AB(School of Mathematics and Statistics,
Newcastle University, Newcastle upon Tyne NE1 7RU,
United Kingdom), AC(School of Mathematics and
Statistics, Newcastle University, Newcastle upon
Tyne NE1 7RU, United Kingdom), AD(Department of
Physics, Engineering Physics and Astronomy, Queen's
University, Kingston, Ontario, Canada K7L 3N6)
Publication: Physical Review A, vol. 79, Issue 5, id. 053615
Publication Date: 05/2009
Origin: APS
Abstract Copyright: (c) 2009: The American Physical Society
DOI: 10.1103/PhysRevA.79.053615
Bibliographic Code: 2009PhRvA..79e3615J
Abstract
We study the dynamics of a vortex in an atomic Bose-condensed gas at
finite temperature within the Zaremba-Nikuni-Griffin formalism. In a
harmonically trapped pancake-shaped condensate, an off-centered vortex
is known to decay by spiraling out toward the edge of the condensate. We
quantify the dependence of this decay on temperature, atomic collisions,
and thermal cloud rotation. Near the trap center where the density
varies slowly, we show that our numerical results agree with the
predictions of the Hall-Vinen phenomenological friction force model used
to describe quantized vorticity in superfluid systems. Our result thus
clarifies the microscopic origin of the friction and provides an ab
initio determination of its value.
Title: Synthesis of ultrasmall magnetic iron oxide
nanoparticles and study of their colloid and surface
chemistry
Authors: Goloverda, Galina; Jackson, Barry; Kidd, Clayton;
Kolesnichenko, Vladimir
Affiliation: Xavier University of Louisiana, Department of
Chemistry, New Orleans, LA 70125, USA. Also
corresponding author. Tel.: +1 504 520 5417..
Corresponding author. Tel.: +1 504 520 5430; fax: +1
504 520 7942.
Publication: Journal of Magnetism and Magnetic Materials, Volume
321, Issue 10, p. 1372-1376.
Publication Date: 05/2009
Origin: ELSEVIER
Abstract Copyright: Elsevier B.V.
DOI: 10.1016/j.jmmm.2009.02.041
Bibliographic Code: 2009JMMM..321.1372G
Abstract
Colloidal nanoparticles of Fe3O4 (4 nm) were
synthesized by high-temperature hydrolysis of chelated iron (II) and
(III) diethylene glycol alkoxide complexes in a solution of the parent
alcohol (H2DEG) without using capping ligands or surfactants:
[Fe(DEG)Cl2]2-+2[Fe(DEG)Cl3]2-+2H2O+2OH--->Fe3O4+3H2DEG+8Cl-
The obtained particles were reacted with different small-molecule
polydentate ligands, and the resulting adducts were tested for aqueous
colloid formation. Both the carboxyl and alpha-hydroxyl groups of the
hydroxyacids are involved in coordination to the nanoparticles'
surface. This coordination provides the major contribution to the
stability of the ligand-coated nanoparticles against hydrolysis.
Title: A Frequency Tripler Using a Subharmonic Mixer and
Fundamental Cancellation
Authors: Jackson, Brad R.; Mazzilli, Francesco;
Saavedra, Carlos E.
Publication: IEEE Transactions on Microwave Theory and
Techniques, vol. 57, issue 5, pp. 1083-1090
Publication Date: 05/2009
Origin: CROSSREF
DOI: 10.1109/TMTT.2009.2017250
Bibliographic Code: 2009ITMTT..57.1083J
Abstract
Not Available
Title: Shoreline features of Titan's Ontario Lacus from
Cassini/VIMS observations
Authors: Barnes, Jason W.; Brown, Robert H.;
Soderblom, Jason M.; Soderblom, Laurence A.;
Jaumann, Ralf; Jackson, Brian; Le Mouélic, Stéphane;
Sotin, Christophe; Buratti, Bonnie J.;
Pitman, Karly M.; Baines, Kevin H.; Clark, Roger N.;
Nicholson, Phillip D.; Turtle, Elizabeth P.;
Perry, Jason
Affiliation: AA(NASA Ames Research Center, Mail Stop 244-30,
Moffett Field, CA 94035, USA; Department of Physics,
University of Idaho, Engineering-Physics Building,
Moscow, ID 83844, USA), AB(Department of Planetary
Sciences, University of Arizona, Tucson, AZ 85721,
USA), AC(Department of Planetary Sciences,
University of Arizona, Tucson, AZ 85721, USA),
AD(United States Geological Survey, Flagstaff, AZ
86001, USA), AE(DLR, Institute of Planetary
Research, Rutherfordstrasse 2, D-12489, Berlin,
Germany), AF(Department of Planetary Sciences,
University of Arizona, Tucson, AZ 85721, USA),
AG(Laboratoire de Planétologie et Géodynamique, CNRS
UMR6112, Université de Nantes, France), AH(Jet
Propulsion Laboratory, California Institute of
Technology, 4800 Oak Grove Drive, Pasadena, CA
91109, USA), AI(Jet Propulsion Laboratory,
California Institute of Technology, 4800 Oak Grove
Drive, Pasadena, CA 91109, USA), AJ(Jet Propulsion
Laboratory, California Institute of Technology, 4800
Oak Grove Drive, Pasadena, CA 91109, USA), AK(Jet
Propulsion Laboratory, California Institute of
Technology, 4800 Oak Grove Drive, Pasadena, CA
91109, USA), AL(United States Geological Survey,
Denver, CO 80225, USA), AM(Department of Astronomy,
Cornell University, Ithaca, NY 14853, USA), AN(Johns
Hopkins University Applied Physics Laboratory, 11100
Johns Hopkins Road, Laurel, MD 20723, USA),
AO(Department of Planetary Sciences, University of
Arizona, Tucson, AZ 85721, USA)
Publication: Icarus, Volume 201, Issue 1, p. 217-225.
Publication Date: 05/2009
Origin: ELSEVIER
DOI: 10.1016/j.icarus.2008.12.028
Bibliographic Code: 2009Icar..201..217B
Abstract
We analyze observations of Titan's south polar lake Ontario Lacus
obtained by Cassini's Visual and Infrared Mapping Spectrometer during
the 38th flyby of Titan (T38; 2007 December 5). These
near-closest-approach observations have the highest signal-to-noise, the
finest spatial resolution, and the least atmospheric influence of any
near-infrared lake observation to date. We use the large, spatially
flat, and low-albedo interior of Ontario Lacus as a calibration target
allowing us to derive an analytical atmospheric correction for emission
angle. The dark lake interior is surrounded by two separate annuli that
follow the lake interior's contours. The inner annulus is uniformly
dark, but not so much as the interior lake, and is generally 5-10
kilometers wide at the lake's southeastern margin. We propose that it
represents wet lakebed sediments exposed by either tidal sloshing of the
lake or seasonal methane loss leading to lower lake-volume. The exterior
annulus is bright and shows a spectrum consistent with a relatively low
water-ice content relative to the rest of Titan. It may represent
fine-grained condensate deposits from a past era of higher lake level.
Together, the annuli seem to indicate that the lake level for Ontario
Lacus has changed over time. This hypothesis can be tested with
observations scheduled for future Titan flybys.
Title: Total mass distributions of Sersic galaxies from
photometry and central velocity dispersion
Authors: Chakrabarty, D.; Jackson, B.
Affiliation: AA(School of Physics & Astronomy, University of
Nottingham, Nottingham NG7 2RD, UK
for Astronomy, University of Edinburgh, Blackford
Publication: Astronomy and Astrophysics, Volume 498, Issue 2,
2009, pp.615-626
Publication Date: 05/2009
Origin: EDP Sciences
Keywords: methods: data analysis, galaxies: fundamental
parameters
DOI: 10.1051/0004-6361/200809965
Bibliographic Code: 2009A&A...498..615C
Abstract
Aims: We develop a novel way of finding total mass density profiles in
Sersic ellipticals, to about 3 times the major axis effective radius,
using no other information other than what is typically available for
distant galaxies, namely the observed surface brightness distribution
and the central velocity dispersion sigma_0.
Methods: The
luminosity density profile of the observed galaxy is extracted by
deprojecting the measured brightness distribution and scaling it by a
fiduciary, step-function shaped, raw mass-to-light ratio profile (M/L).
The resulting raw, discontinuous, total, 3-D mass density profile is
then smoothed according to a proposed smoothing prescription. The
parameters of this raw M/L are characterised by implementing the
observables in a model-based study.
Results: The complete
characterisation of the formalism is provided as a function of the
measurements of the brightness distribution and sigma_0. The
formalism, thus specified, is demonstrated to yield the mass density
profiles of a suite of test galaxies and is successfully applied to
extract the gravitational mass distribution in NGC 3379 and NGC 4499,
out to about 3 effective radii.
Title: The HD 40307 Planetary System: Super-Earths or
Mini-Neptunes?
Authors: Barnes, Rory; Jackson, Brian; Raymond, Sean N.;
West, Andrew A.; Greenberg, Richard
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona, Tucson, AZ 85721, USA ), AB(Lunar and
Planetary Laboratory, University of Arizona, Tucson,
AZ 85721, USA ), AC(Center for Astrophysics and
Space Astronomy, University of Colorado, Boulder, CO
80309, USA; NASA Postdoctoral Program Fellow.),
AD(Astronomy Department, University of California,
601 Campbell Hall, Berkeley, CA 94720-3411, USA ),
AE(Lunar and Planetary Laboratory, University of
Arizona, Tucson, AZ 85721, USA )
Publication: The Astrophysical Journal, Volume 695, Issue 2, pp.
1006-1011 (2009).
Publication Date: 04/2009
Origin: IOP
ApJ Keywords: methods: N-body simulations, planetary systems,
stars: individual: HD 40307
DOI: 10.1088/0004-637X/695/2/1006
Bibliographic Code: 2009ApJ...695.1006B
Abstract
Three planets with minimum masses less than 10 M⊕ orbit
the star HD 40307, suggesting these planets may be rocky. However, with
only radial velocity data, it is impossible to determine if these
planets are rocky or gaseous. Here we exploit various dynamical features
of the system in order to assess the physical properties of the planets.
Observations allow for circular orbits, but a numerical integration
shows that the eccentricities must be at least 10-4.
Also, planets b and c are so close to the star that tidal effects are
significant. If planet b has tidal parameters similar to the terrestrial
planets in the solar system and a remnant eccentricity larger than
10-3, then, going back in time, the system would have
been unstable within the lifetime of the star (which we estimate to be
6.1 ± 1.6 Gyr). Moreover, if the eccentricities are that large
and the inner planet is rocky, then its tidal heating may be an order of
magnitude greater than extremely volcanic Io, on a per unit surface area
basis. If planet b is not terrestrial, e.g., Neptune-like, these
physical constraints would not apply. This analysis suggests the planets
are not terrestrial-like, and are more like our giant planets. In either
case, we find that the planets probably formed at larger radii and
migrated early-on (via disk interactions) into their current orbits.
This study demonstrates how the orbital and dynamical properties of
exoplanet systems may be used to constrain the planets' physical
properties.
Title: On the large-scale instability in interacting dark
energy and dark matter fluids
Authors: Jackson, Brendan M.; Taylor, Andy; Berera, Arjun
Affiliation: AA(Institute for Astronomy, School of Physics and
Astronomy, University of Edinburgh, Royal
Observatory, Blackford Hill, Edinburgh EH9 3HJ,
United Kingdom), AB(Institute for Astronomy, School
of Physics and Astronomy, University of Edinburgh,
Royal Observatory, Blackford Hill, Edinburgh EH9
3HJ, United Kingdom), AA(Institute for Physics,
School of Physics and Astronomy, University of
Edinburgh, James Clerk Maxwell Building, The King's
Buildings, Mayfield Road, Edinburgh EH9 3JZ, United
Kingdom)
Publication: Physical Review D, vol. 79, Issue 4, id. 043526
Publication Date: 02/2009
Origin: APS
DOI: 10.1103/PhysRevD.79.043526
Bibliographic Code: 2009PhRvD..79d3526J
Abstract
Recently, Valiviita et al. [J. Cosmol. Astropart. Phys.1475-7516 07
(2008) 02010.1088/1475-7516/2008/07/020] have reported a large-scale
early-time instability in coupled dark energy and dark matter models. We
take the same form of energy-momentum exchange and specialize to the
case when the interaction rate is proportional to Hubble's
parameter and the dark energy density only. Provided the coupling is
made small enough for a given equation of state parameter, we show that
the instability can be avoided. Expressions are derived for nonadiabatic
modes on superhorizon scales in both the radiation and matter dominated
regimes. We also examine the growth of dark matter perturbations in the
subhorizon limit. There we find that the coupling has almost no effect
upon the growth of structure before dark energy begins to dominate. Once
the Universe begins to accelerate, the relative dark matter density
fluctuations not only cease to grow as in uncoupled models, but actually
decay as the Universe continues to expand.
Title: Methane dissociation on Ni(111) and Pt(111):
Energetic and dynamical studies
Authors: Nave, Sven; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA
Publication: Journal of Chemical Physics, Volume 130, Issue 5,
pp. 054701-054701-14 (2009).
Publication Date: 02/2009
Origin: AIP
Keywords: adsorbed layers, adsorption, band structure,
chemisorption, dissociation, excited states, nickel,
organic compounds, platinum, surface states, total
energy
Abstract Copyright: (c) 2009: American Institute of Physics
DOI: 10.1063/1.3065800
Bibliographic Code: 2009JChPh.130e4701N
Abstract
Electronic structure studies and quantum scattering methods are used to
elucidate the differing reactivities of methane on Ni(111) and Pt(111).
For both surfaces the lowest energy pathway to dissociation is over the
top site, where the static surface barrier to reaction is about 0.14 eV
lower on Pt(111) than on Ni(111). If allowed to relax, both surfaces
exhibit a puckering of the metal atoms in the vicinity of the adsorbates
and at the transition state. Thus, motion of the lattice can change the
barrier to reaction. A quantum model for dissociation is employed that
includes several molecular coordinates, and allows for coupling to the
lattice motion and puckering of the lattice. We find that on Ni(111) the
lattice has time to pucker, increasing the reactivity relative to the
static surface case. The more massive atoms on the Pt(111) surface do
not have time to pucker during the reaction. As both lattices become
vibrationally excited the reactivity increases significantly,
particularly at low incident energies where tunneling dominates. Our
model suggests that tunneling is important for these large barrier
systems, particularly at the relatively low incident energies of the
experiments. Our work also suggests that at the large nozzle
temperatures of the experiments, there are contributions to the total
reactivity from vibrationally excited molecules, particularly for
Ni(111). Our model is in reasonable agreement with the experimental
results for Ni(111), while we significantly underestimate the reactivity
on Pt(111) as well as the difference in reactivity between Ni(111) and
Pt(111). This may result from errors in our total-energy calculations
and/or effects due to motion (tunneling) of the methyl group at the
transition state.
Title: Planetary Transits and Tidal Evolution
Authors: Jackson, Brian; Barne, Rory; Greenberg, Richard
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona 1629 E University Blvd, Tucson AZ 85721-0092
Planetary Laboratory, University of Arizona 1629 E
University Blvd, Tucson AZ 85721-0092 USA
Laboratory, University of Arizona 1629 E University
Blvd, Tucson AZ 85721-0092 USA
Publication: Transiting Planets, Proceedings of the International
Astronomical Union, IAU Symposium, Volume 253, p.
217-229
Publication Date: 02/2009
Origin: CUP
DOI: 10.1017/S1743921308026434
Bibliographic Code: 2009IAUS..253..217J
Abstract
Transiting planets are generally close enough to their host stars that
tides may govern their orbital and thermal evolution. We present
calculations of the tidal evolution of recently discovered transiting
planets and discuss their implications. The tidal heating that
accompanies this orbital evolution can be so great that it controls the
planet's physical properties and may explain the large radii observed in
several cases, including, for example, TrES-4. Also, since a planet's
transit probability depends on its orbit, it evolves due to tides.
Current values depend sensitively on the physical properties of the star
and planet, as well as on the system's age. As a result, tidal effects
may introduce observational biases in transit surveys, which may already
be evident in current observations. Transiting planets tend to be
younger than non-transiting planets, an indication that tidal evolution
may have destroyed many close-in planets. Also the distribution of the
masses of transiting planets may constrain the orbital inclinations of
non-transiting planets.
Title: Dissecting Tcell receptor nanocluster signaling
Authors: Manz, Boryana N.; Jackson, Bryan L.;
Petit, Rebecca S.; Dustin, Michael L.;
Groves, Jay T.
Publication: Biophysical Journal, vol. 96, issue 3, pp. 680a-681a
Publication Date: 02/2009
Origin: CROSSREF
DOI: 10.1016/j.bpj.2008.12.3596
Bibliographic Code: 2009BpJ....96R.680M
Abstract
Not Available
Title: Mutations In Transhydrogenase Change The
Fluorescence Emission State Of Trp72 From 1La To
1Lb.
Authors: Broos, Jaap; Jensen, Karina Tveen;
Strambini, Giovanni B.; Gonelli, Margherita;
Jackson, Baz
Publication: Biophysical Journal, vol. 96, issue 3, pp. 47a-47a
Publication Date: 02/2009
Origin: CROSSREF
DOI: 10.1016/j.bpj.2008.12.139
Bibliographic Code: 2009BpJ....96...47B
Abstract
Not Available
Title: The impact of upland land management on flooding:
results from an improved pasture hillslope
Authors: Marshall, Miles R.; Francis, Oliver J.;
Frogbrook, Zoe L.; Jackson, Bethanna M.;
McIntyre, Neil; Reynolds, Brian; Solloway, Imogen;
Wheater, Howard S.; Chell, Joanne
Publication: Hydrological Processes, vol. 23, issue 3, pp.
464-475
Publication Date: 01/2009
Origin: CROSSREF
DOI: 10.1002/hyp.7157
Bibliographic Code: 2009HyPr...23..464M
Abstract
Not Available
Title: Controllability, Observability, Realizability, and
Stability of Dynamic Linear Systems
Authors: Davis, John M.; Gravagne, Ian A.; Jackson, Billy J.;
Marks, Robert J., II
Publication: eprint arXiv:0901.3764
Publication Date: 01/2009
Origin: ARXIV
Keywords: Mathematics - Optimization and Control, Mathematics
- Dynamical Systems, 93B05, 93B07, 93B20, 93B55,
93D99
Comment: typos corrected; current form is as accepted in
EJDE; Electron. J. Diff. Eqns., Vol. 2009(2009), No.
37, pp. 1-32
Bibliographic Code: 2009arXiv0901.3764D
Abstract
We develop a linear systems theory that coincides with the existing
theories for continuous and discrete dynamical systems, but that also
extends to linear systems defined on nonuniform time domains. The
approach here is based on generalized Laplace transform methods (e.g.
shifts and convolution) from our recent work \cite{DaGrJaMaRa}. We study
controllability in terms of the controllability Gramian and various rank
conditions (including Kalman's) in both the time invariant and time
varying settings and compare the results. We also explore observability
in terms of both Gramian and rank conditions as well as realizability
results. We conclude by applying this systems theory to connect
exponential and BIBO stability problems in this general setting.
Numerous examples are included to show the utility of these results.
Title: Coupled Thermal and Tidal Evolution of Known
Transiting Planets
Authors: Miller, Neil; Fortney, J.; Jackson, B.
Affiliation: AA(UC Santa Cruz), AB(UC Santa Cruz), AC(University
of Arizona)
Publication: American Astronomical Society, AAS Meeting \#213,
\#402.07; Bulletin of the American Astronomical
Society, Vol. 41, p.192; Bulletin of the American
Astronomical Society, Vol. 41, p.192
Publication Date: 01/2009
Origin: AAS
Bibliographic Code: 2009AAS...21340207M
Abstract
A code to compute the coupled planetary orbital, tidal, and thermal
evolution has been constructed based on previous work by Fortney et al.
(2007) and Jackson et al. (2008). The model is tested against the 40
known transiting systems. For each planet we search for a set of initial
orbital parameters and a heavy element core size that allow the planet
to evolve to the current observed radius and orbital parameters. In some
cases tidal heating is capable of increasing the radius of the planet to
agree with the observed value, where a planet with no migration or
heating did not agree. However, there remain cases for which tidal
evolution does not result in agreement between the model and
observation. In these cases the model usually predicts a smaller radius
than observed. Our results suggest either some other mechanism inhibits
cooling of the planet's interior, such as double diffusion, or other
heating sources exist that inflate the planet.
Title: The Effects of Tides on Close-In Exoplanets
Authors: Jackson, Brian; Greenberg, R.; Barnes, R.
Affiliation: AA(University of Arizona), AB(University of
Arizona), AC(University of Arizona)
Publication: American Astronomical Society, AAS Meeting \#213,
\#351.01; Bulletin of the American Astronomical
Society, Vol. 41, p.491; Bulletin of the American
Astronomical Society, Vol. 41, p.491
Publication Date: 01/2009
Origin: AAS
Bibliographic Code: 2009AAS...21335101J
Abstract
Close-in exoplanets tend to have more nearly circular orbits than other
planets. the effects of tides on both the star and the planet are the
likely cause. We model the tidal evolution of observed close-in planets
backward in time for the age of each system, taking into account the
coupling between changes in eccentricity e and semi-major axis a
(Jackson et al. 2008 ApJ 678, 1396). We find their original e-values
were broadly distributed, resembling those of planets beyond the reach
of tides, and suggesting a common formation mechanism. Circularization
can require billions of years, contrary to "circularization
timescale'' arguments. Moreover, tides reduce a, from where planets
were when the protoplanetary nebula dissipated.
Tidal migration is accompanied by internal heating of the planet, which
we find can be significant (Jackson et al. 2008 ApJ 681, 1631). The
anomalously large radii of many transiting planets (but not all) may be
explained by this great tidal heating. Tidal heating should be
incorporated into interior modeling efforts.
For rocky planets, tidal heating is great enough to significantly affect
potential habitability (Jackson et al. 2008 MNRAS, in press). For
hypothetical, rocky planets in the habitable zones of low-mass stars,
tidal heating may be large enough to drive massive volcanism and thus
preclude habitability, or may drive processes (like plate tectonics)
that enhance habitability.
Tidal evolution of orbits must also have destroyed exoplanets that
migrate too close to the host star. The distribution of semi-major axes
and ages suggests that many close planets may have fallen into their
star already. When we apply our tidal model to observed planets, we find
that many young planets may be destroyed in a few billion years. Tidal
destruction may affect stellar rotation, metallicity, and obliquity, and
hence may be a factor in the statistics of these parameters.
Title: Tidal evolution of extra-solar planets
Authors: Jackson, Brian Kendall
Affiliation: AA(The University of Arizona)
Publication: Proquest Dissertations And Theses 2009. Section
0009, Part 0606 199 pages; [Ph.D.
dissertation].United States -- Arizona: The
University of Arizona; 2009. Publication Number: AAT
3356402. Source: DAI-B 70/05, Nov 2009
Publication Date: 00/2009
Origin: UMI
Keywords: Tidal evolution, Extrasolar planets, Eccentric
orbits
Comment: Publication Number: AAT 3356402; ISBN:
9781109166590; Advisor: Greenberg, Richard;
Committee members: Hubbard, William, Lunine,
Jonathan, Showman, Adam, Yelle, Roger, Barnes,
Rory
Bibliographic Code: 2009PhDT.........2J
Abstract
In both our solar system and extra-solar planetary systems, tides may
have a variety of effects, driving complex orbital evolution and
geophysical processes. For extra-solar planets with orbits that pass
very close to their host stars, tides have reduced orbital
eccentricities and semi-major axes, and the rates of tidal evolution may
change dramatically as orbits evolve. Understanding how the orbits have
evolved and, ultimately, discerning the origins of close-in extra-solar
planets require accounting for all the complexity of tidal evolution.
The accompanying dissipation of tidal energy within the planets has
probably also affected their internal structures. In some cases, tidal
dissipation may account the apparent discrepancy between predictions and
observations of the radii of extra-solar planets that transit their host
stars. Evolutionary models for these planets that allow determinations
of their internal structures and composition must include highly
variable tidal heating rates. The same tidal evolution and heating
probably also affects the orbital and geophysical properties of rocky
extra-solar planets and may play a key role in determining whether such
a planet can harbor life. As tides reduce a planet's semi-major axis,
the planet may eventually pass so close to its host star that the star's
gravity completely disrupts the planet, leading to the destruction of
many planets. Tidal destruction has left a discernible signature on the
distribution of extra-solar planetary orbits, and so interpretations of
the distribution in terms of the origins of planets must include
consideration of the effects of tidal destruction.
Title: Mesoscale Convective Systems over Western Equatorial
Africa and Their Relationship to Large-Scale
Circulation
Authors: Jackson, Brian; Nicholson, Sharon E.;
Klotter, Douglas
Publication: Monthly Weather Review, vol. 137, issue 4, p. 1272
Publication Date: 00/2009
Origin: CROSSREF
DOI: 10.1175/2008MWR2525.1
Bibliographic Code: 2009MWRv..137.1272J
Abstract
Not Available
Title: MOS Uncertainty Estimates in an Ensemble Framework
Authors: Glahn, Bob; Peroutka, Matthew; Wiedenfeld, Jerry;
Wagner, John; Zylstra, Greg; Schuknecht, Bryan;
Jackson, Bryan
Publication: Monthly Weather Review, vol. 137, issue 1, p. 246
Publication Date: 00/2009
Origin: CROSSREF
DOI: 10.1175/2008MWR2569.1
Bibliographic Code: 2009MWRv..137..246G
Abstract
Not Available
Title: Solar Mass Ejection Imager 3-D reconstruction of the
27-28 May 2003 coronal mass ejection sequence
Authors: Jackson, B. V.; Bisi, M. M.; Hick, P. P.;
Buffington, A.; Clover, J. M.; Sun, W.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AB(Center for Astrophysics and
Space Sciences, University of California, San Diego,
La Jolla, California, USA); AC(Center for
Astrophysics and Space Sciences, University of
California, San Diego, La Jolla, California, USA);
AD(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AE(Center for Astrophysics and
Space Sciences, University of California, San Diego,
La Jolla, California, USA); AF(Geophysical
Institute, University of Alaska, Fairbanks, Alaska,
USA)
Publication: Journal of Geophysical Research, Volume 113, Issue
52, CiteID A00A15
Publication Date: 12/2008
Origin: AGU
AGU Keywords: Interplanetary Physics: Coronal mass ejections
(7513), Interplanetary Physics: Solar wind plasma,
Paleoceanography: Geochemical tracers, Solar
Physics, Astrophysics, and Astronomy: Coronal mass
ejections (2101), Solar Physics, Astrophysics, and
Astronomy: Instruments and techniques
DOI: 10.1029/2008JA013224
Bibliographic Code: 2008JGRA..11300A15J
Abstract
The Solar Mass Ejection Imager (SMEI) has recorded the
inner-heliospheric response in white-light Thomson scattering for many
hundreds of interplanetary coronal mass ejections (ICMEs). Some of these
have been observed by the Solar and Heliospheric Observatory (SOHO)
Large-Angle Spectroscopic Coronagraph (LASCO) instruments and also in
situ by near-Earth spacecraft. This article presents a low-resolution
three-dimensional (3-D) reconstruction of the 27-28 May 2003 halo CME
event sequence observed by LASCO and later using SMEI observations; this
sequence was also observed by all in situ monitors near Earth. The
reconstruction derives its perspective views from outward flowing solar
wind. Analysis results reveal the shape, extent, and mass of this ICME
sequence as it reaches the vicinity of Earth. The extended shape has
considerable detail that is compared with LASCO images and masses for
this event. The 3-D reconstructed density, derived from the
remote-sensed Thomson scattered brightness, is also compared with the
Advanced Composition Explorer (ACE) and Wind spacecraft in situ plasma
measurements. These agree well in peak and integrated total value for
this ICME event sequence when an appropriately enhanced (~20%) electron
number density is assumed to account for elements heavier than hydrogen
in the ionized plasma.
Title: Solar Wind 3D Reconstructions of the Whole
Heliospheric Interval
Authors: Bisi, M. M.; Jackson, B. V.; Clover, J. M.;
Hick, P. P.; Buffington, A.; Manoharan, P. K.;
Tokumaru, M.
Affiliation: AA(Center for Astrophysics and Space Sciences (CASS)
- University of California at San Diego (UCSD), 9500
Gilman Drive \#0424, La Jolla, CA 92093-0424, United
Astrophysics and Space Sciences (CASS) - University
of California at San Diego (UCSD), 9500 Gilman Drive
\#0424, La Jolla, CA 92093-0424, United States;
and Space Sciences (CASS) - University of California
at San Diego (UCSD), 9500 Gilman Drive \#0424, La
Jolla, CA 92093-0424, United States;
Space Sciences (CASS) - University of California at
San Diego (UCSD), 9500 Gilman Drive \#0424, La Jolla,
AE(Center for Astrophysics and Space Sciences (CASS)
- University of California at San Diego (UCSD), 9500
Gilman Drive \#0424, La Jolla, CA 92093-0424, United
Centre - National Centre for Radio Astrophysics,
Tata Institute of Fundamental Research,
Udhagamandalam(Ooty), 643 001, India;
Environment Laboratory - Nagoya University, Furo-cho
Chikusa-ku, Nagoya, 464-8601, Japan;
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#SH23A-1617
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 2100 INTERPLANETARY PHYSICS, 2101 Coronal mass
ejections (7513), 2102 Corotating streams, 2199
General or miscellaneous, 7599 General or
miscellaneous
Bibliographic Code: 2008AGUFMSH23A1617B
Abstract
3D tomographic reconstructions of the inner heliosphere have been used
for over a decade to visualise and investigate the structure of the
solar wind and its various features such as transients and corotating
structures. Interplanetary scintillation (IPS) observations of the solar
wind have been carried out for a much longer period of time revealing
information on the structure of the solar wind and the features within
it. Here we present such 3D reconstructions using IPS observations from
the Solar Terrestrial Environment Laboratory (STELab) and the Ootacamund
(Ooty) Radio Telescope (ORT) of the Whole Heliospheric Interval (WHI)
Carrington Rotation 2068. This is part of the world-wide IPS community's
International Heliosphysical Year (IHY) collaboration. We show the
structure of the inner heliosphere during this time and how our global
reconstructions compare with deep-space spacecraft measurements such as
those taken by Wind, ACE, STEREO, and Ulysses in terms of density and
velocity.
Title: Measurements of the Gegenschein brightness from the
Solar Mass Ejection Imager (SMEI)
Authors: Buffington, A.; Bisi, M. M.; Clover, J. M.; Hick, P.;
Jackson, B. V.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, 9500 Gilman
Drive, La Jolla, CA 92093-0424, United States;
and Space Sciences, University of California at San
Diego, 9500 Gilman Drive, La Jolla, CA 92093-0424,
Astrophysics and Space Sciences, University of
California at San Diego, 9500 Gilman Drive, La
Jolla, CA 92093-0424, United States;
Space Sciences, University of California at San
Diego, 9500 Gilman Drive, La Jolla, CA 92093-0424,
Astrophysics and Space Sciences, University of
California at San Diego, 9500 Gilman Drive, La
Jolla, CA 92093-0424, United States;
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#SH13B-1561
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 2129 Interplanetary dust, 6213 Dust, 7599 General or
miscellaneous
Bibliographic Code: 2008AGUFMSH13B1561B
Abstract
The Gegenschein is a faint diffuse component of the zodiacal light
centered upon the antisolar point; this has now been viewed by the
Solar Mass Ejection Imager (SMEI) for over 5 years. SMEI provides
unprecedented near-full-sky photometric maps each 102-minute orbit,
using data from 3 unfiltered CCD cameras. Its 0.1% photometric precision
enables observation over long periods of time, of heliospheric
structures having surface brightness down to several S10's (an S10 is
the equivalent brightness of a 10th magnitude star spread over one
square degree). When individual bright stars are removed from the maps
and an empirical sidereal background subtracted, the residue is
dominated by the zodiacal light. The sky coverage and duration of these
measurements enables a definitive characterization. We describe the
analysis method for these data, characterize the average Gegenschein
brightness distribution, present empirical formulae describing its
shape, and discuss its variation with time.
Title: SMEI Remote Sensing and the 3D Reconstruction of
Corotating Heliospheric Structures
Authors: Jackson, B. V.; Bisi, M. M.; Hick, P. P.;
Buffington, A.; Clover, J. M.; Webb, D. F.;
Tokumaru, M.; Manoharan, P. K.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AB(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
for Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093, United
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093, United
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093, United
Scientific Research, Boston College, Chestnut Hill,
MA 02467, United States;
Environment Laboratory, Nagoya University, Furo-cho,
Chikusa-ku, Nagoya, 464-8601, Japan;
Astronomy Centre, National Centre for Radio
Astrophysics, Tata Institute of Fundamental
Research, Udhagamandalam, (Ooty), 643 001, India;
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#SH13B-1554
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 2102 Corotating
streams, 2164 Solar wind plasma, 2169 Solar wind
sources, 7511 Coronal holes
Bibliographic Code: 2008AGUFMSH13B1554J
Abstract
We report observations and 3D reconstructions of corotating heliospheric
structures observed by the Solar Mass Ejection Imager (SMEI).
Observations of the inner heliosphere have been carried out on a routine
basis by SMEI since its launch in early 2003, and these have been used
to measure and map the outward flow of several-hundred CMEs. Most of
these observations use short-term variations of brightness from one SMEI
orbit to the next (every 102 minutes) to track outward motion. The
disadvantage of these orbit-to-orbit analyses is that they cannot
measure features that remain stationary relative to the Sun-Earth line
(or those which corotate with the Sun) and change slowly over time
periods of several days. At UCSD we provide measurements of
heliospheric structures relative to a long-term base and, even in these
observations, there is little evidence of long-term stationary-standing
density structures that corotate. By employing a kinematic model of the
solar wind, we reconstruct three-dimensional (3D) solar wind structures
from multiple observing lines of sight through the outward-flowing solar
wind. By including interplanetary scintillation (IPS) velocity
observations from STELab, Japan or from Ooty, India we can extract both
the solar wind density and velocity from these analyses to compare with
"ground truth" measurements from multi-point, in-situ solar wind
measurements from the STEREO, SOHO, Wind, and ACE spacecraft. We define
the heliospheric structures by these 3D velocity analyses, and they show
that while the velocities map large regions near the ecliptic that
corotate, the dense structures that front and follow these regions are
far more tenuous.
Title: Modeling the Corona-Heliosphere Interface in
Anticipation of the Murchison Wide-field Array
Authors: Kasper, J. C.; Oberoi, D.; Salah, J. E.;
Jackson, B. V.; Cairns, I.
Affiliation: AA(Smithsonian Astrophysical Observatory, Mail Stop
58 60 Garden Street, Cambridge, MA 02138, United
Observatory, Route 40, Westford, MA 01886, United
AC(MIT-Haystack Observatory, Route 40, Westford, MA
AD(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AE(University of Sydney, NSW, Sydney, 2006,
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#SH11A-03
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 7509 Corona,
7524 Magnetic fields, 7534 Radio emissions, 7827
Kinetic and MHD theory
Bibliographic Code: 2008AGUFMSH11A..03K
Abstract
The Murchison Widefield Array (MWA) is an 8,000-antenna, 80-300 MHz,
imaging radio array under construction in Western Australia that
features a large field of view, high sensitivity, and accurate
polarization and intensity calibration. An MWA prototype has been
deployed in the field and construction of the full array will begin in
mid-2009 after the performance of the prototype is evaluated.
Understanding the connection between the upper corona and the inner
heliosphere with novel low-frequency radio observations is a primary
objective of the MWA Solar, Heliospheric, and Ionospheric (SHI) science
consortium. This presentation covers progress by the SHI consortium's
theory and modeling effort. We show simulations of how Faraday
rotation, interplanetary scintillation, and radio burst measurements can
track and constrain the transport of magnetic fields, density, and
energetic electrons into the heliosphere.
Title: Observation and Modeling of Ion Upwelling Above
Aurora
Authors: Lummerzheim, D.; Otto, A.; Doe, R. A.;
Jackson, B. V.; Mizuno, D.; Webb, D. F.;
Collins, R. L.; Light, A. S.
Affiliation: AA(Geophysical Institute, University of Alaska,
Fairbanks, AK 99775-7320, United States;
University of Alaska, Fairbanks, AK 99775-7320,
Ravenwood Ave, Menlo Park, CA 94025, United States;
San Diego, 9500 Gilman Dr, La Jolla, CA 92093-0424,
Boston College, 140 Commenwealth Ave, Chestnut Hill,
MA 02467-3862, United States;
College, 140 Commenwealth Ave, Chestnut Hill, MA
02467-3862, United States;
Institute, University of Alaska, Fairbanks, AK
AH(Geophysical Institute, University of Alaska,
Fairbanks, AK 99775-7320, United States;
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#SA21B-1542
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 0310 Airglow and aurora, 0355 Thermosphere:
composition and chemistry, 0358 Thermosphere: energy
deposition (3369), 2407 Auroral ionosphere (2704)
Bibliographic Code: 2008AGUFMSA21B1542L
Abstract
Auroral electron precipition heats the ionospheric plasma. Especially at
F-region altitudes, this leads to increased plasma pressure and a
pressure gradient force that accelerates plasma away from the heated
region. The resulting upward ion velocities have been observed by the
incoherent scatter radar at Poker Flat (PFISR). The upward moving ions
cause an increased ion density well above typical auroral ionization
altitudes. N2+ ions that are lifted to altitudes above the shadowheight
will resonantly scatter sunlight. This is observed by coincident
overflights of the Solar Mass Ejection Imager (SMEI) on the Coriolis
satellite, looking up from 840 km altitude. We will present a study that
combines modeling and observations by PFISR and SMEI to illustrate and
explain this process.
Title: Disentangling uncertainties in model inputs and
model structure
Authors: Jackson, B.; Clark, M. P.; Kavetski, D.;
McMillan, H.
Affiliation: AA(SGEES, Victoria University, Wellington, 1000, New
Kyle Street Riccarton, Christchurch, 8004, New
Engineering, University of Newcastle, Newcastle, NSW
AD(NIWA, 10 Kyle Street Riccarton, Christchurch,
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#H51E-0874
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 1833 Hydroclimatology, 1846 Model calibration
(3333), 1847 Modeling, 1848 Monitoring networks,
1873 Uncertainty assessment (3275)
Abstract Copyright: (c) 2008: American Geophysical Union
Bibliographic Code: 2008AGUFM.H51E0874J
Abstract
The BATEA method (Bayesian Total Error Analysis) is one of the first
attempts to provide a rigorous assessment of the different sources of
uncertainty in hydrological models. However, separating the role of
uncertainty in model inputs and model structure is problematic because
the structure of a hydrological model (and its parameters) can
compensate for uncertainties in model inputs. This presentation will
evaluate differences between BATEA uncertainty estimates obtained with
different model structures, and will compare BATEA estimates of input
uncertainty with uncertainty estimates obtained using probabilistic
quantitative precipitation estimates.
Title: Internal Catchment Data for Improved Model Diagnosis
and Calibration
Authors: Goodrich, D. C.; Srinivasan, M.; McMillan, H.;
Duncan, M.; Yatheendradas, S.; Wagener, T.;
Clark, M.; Mart{\'{\i}}nez, G.; Gupta, H.; Jackson, B.;
Schmidt, J.; Woods, R.
Affiliation: AA(USDA-ARS-SWRC, 2000 E. Allen Rd., Tucson, AZ
85719, United States;
Street, Christchurch, 8011, New Zealand;
Christchurch, 8011, New Zealand;
Christchurch, 8011, New Zealand;
614.3, Greenbelt, MD 20771, United States;
Sackett Building, University Park, PA 16802, United
Univ., 212 Sackett Building, University Park, PA
16802, United States; NIWA, 10 Kyle Street,
Christchurch, 8011, New Zealand;
P.O. Box 210011, Tucson, AZ 85721, United States;
P.O. Box 210011, Tucson, AZ 85721, United States;
PO Box 600, Wellington, 6140, New Zealand;
Street, Christchurch, 8011, New Zealand;
Christchurch, 8011, New Zealand;
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#H43D-1038
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 1800 HYDROLOGY, 1804 Catchment, 1847 Modeling
Abstract Copyright: (c) 2008: American Geophysical Union
Bibliographic Code: 2008AGUFM.H43D1038G
Abstract
There have been numerous calls for the need to incorporate internal
catchment observations for improving distributed catchment models.
Recent results from a synthetic study by van Werkhoven et al., (GRL,
2008) imply that the relative worth of internal catchment observations
for providing information to improve downstream predictions is limited
to a time-varying zone, or cone of influence - that is, different
observing points have explanatory power for different parts of the
catchment at different times. In their study the spatial extent of
this cone of influence is significantly influenced by a number of
factors; primarily spatiotemporal precipitation patterns; but also
initial conditions and inherent observational and model uncertainties.
To explore this concept further two intensively instrumented
experimental catchments, near end members of the hydro-climatic
spectrum, with extensive internal observations were selected. The first
is the 50 square kilometer Mahurangi Experimental Catchment located on
the north island of New Zealand with mean annual rainfall and runoff of
approximately 1700, and 870 mm, respectively. The second is the 148
square kilometer Walnut Gulch Experimental Watershed located in
southeast Arizona, USA with respective mean annual rainfall and runoff
of 325, and 2 mm. Data analysis and stepwise, spatially-explicit model
calibration was conducted in each of these watersheds. Results from
these analyses, in the context of the worth of internal runoff
observations will be presented. van Werkhoven, K., T. Wagener, P. Reed,
and Y. Tang (2008), Rainfall characteristics define the value of
streamflow observations for distributed watershed model identification,
Geophys. Res. Lett., 35, L11403, doi:10.1029/2008GL034162.
Title: A national hydrological model for New Zealand
Authors: Clark, M. P.; Mart{\'{\i}}nez, G.; McMillan, H.;
Jackson, B.; Gupta, H. V.; Goodrich, D.;
Srinivasan, M.; Schmidt, J.; Woods, R.
Affiliation: AA(NIWA, 10 Kyle Street Riccarton, Christchurch,
AB(Department of Hydrology and Water Resources, The
University of Arizona, Tucson, AZ 85721, United
Street Riccarton, Christchurch, 8004, New Zealand;
University, Wellington, 1000, New Zealand;
Hydrology and Water Resources, The University of
Arizona, Tucson, AZ 85721, United States;
Research Service, 2000 East Allen Road, Tucson, AZ
85719, United States;
Street Riccarton, Christchurch, 8004, New Zealand;
Riccarton, Christchurch, 8004, New Zealand;
Riccarton, Christchurch, 8004, New Zealand;
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#H21K-04
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 1833 Hydroclimatology, 1846 Model calibration
(3333), 1847 Modeling, 1873 Uncertainty assessment
(3275), 1874 Ungaged basins
Abstract Copyright: (c) 2008: American Geophysical Union
Bibliographic Code: 2008AGUFM.H21K..04C
Abstract
New Zealand is a fascinating laboratory for hydrological research. The
land area of New Zealand is relatively small (269,000 km2), but within
this area there are large differences in precipitation (300 to 12,000
mm/year), vegetation (rainforest, grassland, and desert), and geology
(sandstone, pumice, and limestone). Snow can be an important component
of the hydrological budget in the Southern Alps, and streamflow in many
parts of New Zealand is affected by natural and managed lakes. River
forms vary from steep mountain torrents to wide, braided, gravel beds.
There are increasing demands for the available water resources and
increasing vulnerability to floods, and a national hydrological model is
needed for both water resource assessments and flood forecasting. This
presentation discusses the use of research conducted as part of the
Problem of Ungauged Basins (PUB) initiative to build a national
hydrological model for New Zealand. The research has two main steps:
(1) evaluate model simulations in experimental watersheds and use
internal catchment observations of soil moisture, groundwater levels,
and streamflow to identify appropriate model structure(s) and model
parameters; and (2) evaluate the spatial patterns of nationwide model
simulations and use hydrological classification systems to understand
spatial differences in model performance. Nationwide hydrological
datasets and modeling systems are already developed in New Zealand, and
we invite the community to use this "virtual laboratory" for their own
research.
Title: A multi-scale modelling procedure to quantify
hydrological impacts of upland land management
Authors: Wheater, H. S.; Jackson, B.; Bulygina, N.;
Ballard, C.; McIntyre, N.; Marshall, M.;
Frogbrook, Z.; Solloway, I.; Reynolds, B.
Affiliation: AA(IMPERIAL COLLEGE, Dept of Civil and Environmental
Engineering, London, SW7 2AZ, United Kingdom;
Dept of Civil and Environmental Engineering, London,
SW7 2AZ, United Kingdom; ), AC(IMPERIAL COLLEGE,
Dept of Civil and Environmental Engineering, London,
SW7 2AZ, United Kingdom; ), AD(IMPERIAL COLLEGE,
Dept of Civil and Environmental Engineering, London,
SW7 2AZ, United Kingdom; ), AE(IMPERIAL COLLEGE,
Dept of Civil and Environmental Engineering, London,
SW7 2AZ, United Kingdom; ), AF(IMPERIAL COLLEGE,
Dept of Civil and Environmental Engineering, London,
SW7 2AZ, United Kingdom; ), AG(CEH BANGOR,
Environment Centre Wales Deiniol Road, Bangor, LL57
2UW, United Kingdom; ), AH(IMPERIAL COLLEGE, Dept
of Civil and Environmental Engineering, London, SW7
2AZ, United Kingdom; ), AI(CEH BANGOR, Environment
Centre Wales Deiniol Road, Bangor, LL57 2UW, United
Kingdom; )
Publication: American Geophysical Union, Fall Meeting 2008,
abstract \#H12A-07
Publication Date: 12/2008
Origin: AGU
AGU Keywords: 0430 Computational methods and data processing, 1847
Modeling, 1849 Numerical approximations and
analysis, 1894 Instruments and techniques: modeling,
1895 Instruments and techniques: monitoring
Abstract Copyright: (c) 2008: American Geophysical Union
Bibliographic Code: 2008AGUFM.H12A..07W
Abstract
Recent UK floods have focused attention on the effects of agricultural
intensification on flood risk. However, quantification of these effects
raises important methodological issues. Catchment-scale data have proved
inadequate to support analysis of impacts of land management change, due
to climate variability, uncertainty in input and output data, spatial
heterogeneity in land use and lack of data to quantify historical
changes in management practices. Manipulation experiments to quantify
the impacts of land management change have necessarily been limited and
small scale, and in the UK mainly focused on the lowlands and arable
agriculture. There is a need to develop methods to extrapolate from
small scale observations to predict catchment-scale response, and to
quantify impacts for upland areas. With assistance from a cooperative of
Welsh farmers, a multi-scale experimental programme has been established
at Pontbren, in mid-Wales, an area of intensive sheep production. The
data have been used to support development of a multi-scale modelling
methodology to assess impacts of agricultural intensification and the
potential for mitigation of flood risk through land use management.
Data are available from replicated experimental plots under different
land management treatments, from instrumented field and hillslope sites,
including tree shelter belts, and from first and second order
catchments. Measurements include climate variables, soil water states
and hydraulic properties at multiple depths and locations, tree
interception, overland flow and drainflow, groundwater levels, and
streamflow from multiple locations. Fine resolution physics-based models
have been developed to represent soil and runoff processes, conditioned
using experimental data. The detailed models are used to calibrate
simpler 'meta- models' to represent individual hydrological elements,
which are then combined in a semi-distributed catchment-scale model. The
methodology is illustrated using field and catchment-scale simulations
to demonstrate the the response of improved and unimproved grassland,
and the potential effects of land management interventions, including
farm ponds, tree shelter belts and buffer strips. It is concluded that
the methodology developed has the potential to represent and quantify
catchment-scale effects of upland management; continuing research is
extending the work to a wider range of upland environments and land use
types, with the aim of providing generic simulation tools that can be
used to provide strategic policy guidance.
Title: Tidal heating of terrestrial extrasolar planets and
implications for their habitability
Authors: Jackson, Brian; Barnes, Rory; Greenberg, Richard
Affiliation: AA(University of Arizona, Lunar and Planetary
Laboratory, 1629 E. University Blvd, Tucson, AZ
85721-0092, USA; ), AB(University of Arizona, Lunar
and Planetary Laboratory, 1629 E. University Blvd,
Tucson, AZ 85721-0092, USA; ), AC(University of
Arizona, Lunar and Planetary Laboratory, 1629 E.
University Blvd, Tucson, AZ 85721-0092, USA; )
Publication: Monthly Notices of the Royal Astronomical Society,
Volume 391, Issue 1, pp. 237-245.
Publication Date: 11/2008
Origin: MNRAS
MNRAS Keywords: astrobiology, celestial mechanics, planetary
systems
DOI: 10.1111/j.1365-2966.2008.13868.x
Bibliographic Code: 2008MNRAS.391..237J
Abstract
The tidal heating of hypothetical rocky (or terrestrial) extrasolar
planets spans a wide range of values depending on stellar masses and
initial orbits. Tidal heating may be sufficiently large (in many cases,
in excess of radiogenic heating) and long-lived to drive plate
tectonics, similar to the Earth's, which may enhance the planet's
habitability. In other cases, excessive tidal heating may result in
Io-like planets with violent volcanism, probably rendering them
unsuitable for life. On water-rich planets, tidal heating may generate
subsurface oceans analogous to Europa's with similar prospects for
habitability. Tidal heating may enhance the outgassing of volatiles,
contributing to the formation and replenishment of a planet's
atmosphere. To address these issues, we model the tidal heating and
evolution of hypothetical extrasolar terrestrial planets. The results
presented here constrain the orbital and physical properties required
for planets to be habitable.
Title: PHD TUTORIAL: Finite-temperature models of Bose
Einstein condensation
Authors: Proukakis, Nick P.; Jackson, Brian
Affiliation: School of Mathematics and Statistics, Newcastle
University, Newcastle-upon-Tyne NE1 7RU, UK
Publication: Journal of Physics B: Atomic, Molecular, and Optical
Physics, Volume 41, Issue 20, pp. 203002 (2008).
Publication Date: 10/2008
Origin: IOP
DOI: 10.1088/0953-4075/41/20/203002
Bibliographic Code: 2008JPhB...41t3002P
Abstract
The theoretical description of trapped weakly interacting
Bose--Einstein condensates is characterized by a large number of
seemingly very different approaches which have been developed over the
course of time by researchers with very distinct backgrounds. Newcomers
to this field, experimentalists and young researchers all face a
considerable challenge in navigating through the 'maze' of abundant
theoretical models, and simple correspondences between existing
approaches are not always very transparent. This tutorial provides a
generic introduction to such theories, in an attempt to single out
common features and deficiencies of certain 'classes of approaches'
identified by their physical content, rather than their particular
mathematical implementation. This tutorial is structured in a manner
accessible to a non-specialist with a good working knowledge of quantum
mechanics. Although some familiarity with concepts of quantum field
theory would be an advantage, key notions, such as the occupation number
representation of second quantization, are nonetheless briefly reviewed.
Following a general introduction, the complexity of models is gradually
built up, starting from the basic zero-temperature formalism of the
Gross--Pitaevskii equation. This structure enables readers to probe
different levels of theoretical developments (mean field, number
conserving and stochastic) according to their particular needs. In
addition to its 'training element', we hope that this tutorial will
prove useful to active researchers in this field, both in terms of the
correspondences made between different theoretical models, and as a
source of reference for existing and developing finite-temperature
theoretical models.
Title: Three-dimensional reconstructions of the early
November 2004 Coordinated Data Analysis Workshop
geomagnetic storms: Analyses of STELab IPS speed and
SMEI density data
Authors: Bisi, M. M.; Jackson, B. V.; Hick, P. P.;
Buffington, A.; Odstrcil, D.; Clover, J. M.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AB(Center for Astrophysics and
Space Sciences, University of California, San Diego,
La Jolla, California, USA); AC(Center for
Astrophysics and Space Sciences, University of
California, San Diego, La Jolla, California, USA);
AD(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AE(Space Weather Prediction
Center, National Oceanic and Atmospheric
Administration, Boulder, Colorado, USA); AF(Center
for Astrophysics and Space Sciences, University of
California, San Diego, La Jolla, California, USA)
Publication: Journal of Geophysical Research, Volume 113, Issue
52, CiteID A00A11
Publication Date: 10/2008
Origin: AGU
AGU Keywords: Interplanetary Physics: Coronal mass ejections
(7513), Space Weather: Magnetic storms (2788), Solar
Physics, Astrophysics, and Astronomy: General or
miscellaneous, Interplanetary Physics: Instruments
and techniques, Radio Science: Remote sensing
DOI: 10.1029/2008JA013222
Bibliographic Code: 2008JGRA..11300A11B
Abstract
Combined interplanetary scintillation (IPS) and Solar Mass Ejection
Imager (SMEI) remote-sensing observations provide a view of the solar
wind at almost all heliographic latitudes and covering distances from
the Sun between 0.1 AU and 3.0 AU. They are used to study the
development of the solar wind and coronal transients as they move out
into interplanetary space, and also the inner heliospheric response to
the passage of corotating solar structures and coronal mass ejections
(CMEs). The observations take place in both radio scintillation level
and speed for IPS, and in Thomson-scattered white light brightness for
SMEI. With colleagues at the Solar Terrestrial Environment Laboratory
(STELab), Nagoya University, Japan, we have developed a data analysis
system for the STELab IPS data which can also be applied to SMEI white
light data. This employs a three-dimensional (3-D) reconstruction
technique that obtains perspective views from solar corotating plasma
and outward flowing solar wind as observed from the Earth by iterative
fitting of a kinematic solar wind model to the data. This 3-D modeling
technique permits reconstructions of the density and speed of CMEs and
other interplanetary transients at relatively coarse spatial and
temporal resolutions. For the time-dependent model (used here), these
typically range from 5° to 20° in latitude and longitude, with a
1/2 to 1 day time cadence. For events during early November 2004 we
compare these reconstructed structures with in situ measurements from
the ACE and Wind (near-Earth) spacecraft to validate the 3-D tomographic
reconstruction results and provide input to the ENLIL 3-D
magnetohydrodynamic (MHD) numerical model.
Title: Complex zero-free regions at large |q| for
multivariate Tutte polynomials (alias Potts-model
partition functions) with general complex edge
weights
Authors: Jackson, Bill; Procacci, Aldo; Sokal, Alan D.
Publication: eprint arXiv:0810.4703
Publication Date: 10/2008
Origin: ARXIV
Keywords: Mathematics - Combinatorics, Mathematical Physics,
05C15 (Primary), 05A20, 05B35, 05C99, 05E99, 30C15,
82B20 (Secondary)
Comment: LaTeX2e, 34 pages. Version 2 improves Theorem 1.3,
using an improved Proposition 4.4 and a new
Proposition 5.2
Bibliographic Code: 2008arXiv0810.4703J
Abstract
We find zero-free regions in the complex plane at large |q| for the
multivariate Tutte polynomial (also known in statistical mechanics as
the Potts-model partition function) Z_G(q,w) of a graph G with general
complex edge weights w = {w_e}. This generalizes a result of Sokal
(cond-mat/9904146) that applied only within the complex
antiferromagnetic regime |1+w_e| \le 1. Our proof uses the polymer-gas
representation of the multivariate Tutte polynomial together with the
Penrose identity.
Title: Evidence for Past Lake-Level Change in Titan's
Ontario Lacus
Authors: Barnes, Jason W.; Brown, R. H.; Soderblom, J. M.;
Soderblom, L. A.; Jaumann, R.; Jackson, B.;
Le Mouelic, S.; Sotin, C.; Buratti, B. J.;
Pitman, K. M.; Baines, K. H.; Clark, R. N.;
Nicholson, P. D.; Turtle, E. P.; Perry, J.
Affiliation: AA(University of Idaho), AB(University of Arizona),
AC(University of Arizona), AD(USGS), AE(DLR,
Germany), AF(University of Arizona), AG(University
de Nantes, France), AH(JPL), AI(JPL), AJ(JPL),
AK(JPL), AL(USGS), AM(Cornell), AN(APL),
AO(University of Arizona)
Publication: American Astronomical Society, DPS meeting \#40,
\#23.08; Bulletin of the American Astronomical
Society, Vol. 40, p.429
Publication Date: 09/2008
Origin: AAS
Bibliographic Code: 2008DPS....40.2308B
Abstract
Cassini Visual and Infrared Mapping Spectrometer (VIMS) observations of
Titan's south-polar lake Ontario Lacus obtained during the T38 (2008
December 7) encounter represent the finest spatial resolution, highest
signal to noise ratio, and least atmospheric component of any
near-infrared lake data to date. These data have recently confirmed the
liquid nature of Titan's putative lakes (Brown et al. 2008 July,
_Nature_). Here we investigate the geomorphology of the lake's shoreline
using the VIMS T38 data, with Imaging Science Subsystem (ISS)
observations for context. We find that the dark, liquid interior of
Ontario Lacus is surrounded by two brighter annuli. The inner annulus is
dark, though not so much as the lake's core, varies between 5 and 10 km
in width, and may comprise wet lakebed sediments exposed by seasonal
lowering of the lake level. The outer annulus is brighter and free of
water ice, according to the spectral signature. The width of the outer
annulus varies from several hundred meters to 20 km. The nature of
these bright deposits is not clear, but they may indicate fine-grained
organic condensates deposited during an earlier era of higher lake
level. We will discuss the dataset and image processing, along with
various hypotheses for formation of the annuli, concluding with the
implications of our interpretations for Titan's methane cycle and future
Cassini observations.
Title: Jupiter's Tidal Q: The Range of Uncertainty
Authors: Greenberg, Richard; Barnes, R.; Jackson, B.
Affiliation: AA(Univ. of Arizona), AB(Univ. of Arizona), AC(Univ.
of Arizona)
Publication: American Astronomical Society, DPS meeting \#40,
\#4.03; Bulletin of the American Astronomical
Society, Vol. 40, p.391
Publication Date: 09/2008
Origin: AAS
Bibliographic Code: 2008DPS....40.0403G
Abstract
Jupiter's Q, which quantifies the net effect of poorly understood
dissipative processes, is central to the physical and orbital history of
the Galilean satellites and to studies of extra-solar planets. A
standard procedure for determining orbits from observations of
extra-solar planets is to estimate e-damping times, using for Q a
"commonly accepted value'' 105-106, based on
supposed constraints on Jupiter's Q: If the damping time is short,
orbits are assumed circular; if the data nevertheless require a finite
e, it is attributed to perturbations by unseen planets. But those
now-standard procedures are flawed because, in fact, there are no firm
constraints on Jupiter's Q.
Given the dynamics of the system and its Laplace resonance, knowledge of
the tidal dissipation rate in Io (from heat flux) and of Io's orbital
acceleration dn1/dt (from mutual occultations and eclipses)
should determine the effective value of QJ. If the Laplace
resonance were in an equilibrium steady-state, then either one of those
measured values yield QJ. Aksnes and Franklin's
("A&F's'' 2001) solution for dn1/dt of
3.6x10-10/yr and McEwen et al.'s (1992) Io heat flux
1.3x1014W, gives QJ=2x105, the solution
A&F highlighted. However, slight changes from those measured values,
well within the uncertainty range, would yield infinite QJ.
Another fit to the mutual event data allowed dn1/dt=0, but
A&F rejected this result because the implied QJ ( 3x104)
was outside the conventionally accepted range. In fact, that range is
based on the steady-state condition of the resonance (placing an upper
limit on QJ) and on the assumption that
dn1/dt<0; (which gives a lower limit), both of which are
ruled out by A&F's results. Our study of tidal evolution of "hot
Jupiters'' (Jackson et al. 2008) suggests typical Q values of
106.5, somewhat above the widely assumed range, but below the
real upper limit (infinity) for Jupiter.
Title: Tidal Heating of Extrasolar Terrestrial-scale
Planets and Constraints on Habitability
Authors: Jackson, Brian; Barnes, R.; Greenberg, R.
Affiliation: AA(University of Arizona), AB(University of
Arizona), AC(University of Arizona)
Publication: American Astronomical Society, DPS meeting \#40,
\#4.02; Bulletin of the American Astronomical
Society, Vol. 40, p.391
Publication Date: 09/2008
Origin: AAS
Bibliographic Code: 2008DPS....40.0402J
Abstract
Tidal evolution of rocky ("terrestrial") extrasolar planets can generate
significant internal heating. For example, if the recently-discovered
super-Earths, such as GJ 876 d, Gl 581 c and HD 40307 b, are indeed
terrestrial, their internal heating may be large enough to melt them, or
at least produce Io-like volcanism, which would dim their prospects for
habitability. Because tidal heating scales with planet mass, we expect
most detectable super-Earths will be similarly dominated by volcanic
activity. Such volcanic activity may be apparent in transit spectra.
However, the tidal heating of hypothetical terrestrial-type extra-solar
planets may span many orders of magnitude, depending on their physical
and orbital properties. For a wide range of parameter values, rather
than inducing global volcanism, more moderate tidal heating may drive
plate tectonics, similar to the Earth's, fulfilling one possible
requirement for habitability. On planets with insufficient radiogenic
heating for plate tectonics, such as extrasolar dwarf planets, tidal
heating may thus be essential for habitability. Tidal heating may also
enhance the outgassing of volatiles, contributing to the formation and
replenishment of a planet's atmosphere. On water-rich rocky planets,
tidal heating may generate sub-surface oceans analogous to Europa's and
with similar prospects for habitability. We quantify heating rates (and
the change in these rates over time) for a range of physical and orbital
parameters and identify which combinations could lead to planets with
insufficient tidal heat for tectonics; planets with so much heat that
there could be excessive volcanism; or the planets that are just right,
with just enough tidal heat to experience plate tectonics and thus be
candidates for habitability. This research demonstrates how the orbital
properties of extrasolar planetary systems may be used to constrain the
planets' physical properties.
Title: Coupled Orbital and Thermal Evolution of Transiting
Planet TrES-4
Authors: Miller, Neil; Fortney, J.; Jackson, B.
Affiliation: AA(UC Santa Cruz), AB(UC Santa Cruz), AC(Lunar and
Planetary Lab, University of Arizona)
Publication: American Astronomical Society, DPS meeting \#40,
\#1.09; Bulletin of the American Astronomical
Society, Vol. 40, p.387
Publication Date: 09/2008
Origin: AAS
Bibliographic Code: 2008DPS....40.0109M
Abstract
The hot Jupiter planet TrES-4 currently has a radius of 1.75 Jupiter
radii, making it the largest known transiting planet. Explaining this
large radius represents a theoretical challenge. Our goal is to find a
self-consistent orbital and thermal evolution history of this planet
that is consistent with the observed semimajor axis, eccentricity and
radius. We have performed the first calculations of TrES-4's thermal
evolution that incorporate the planet's tidal and orbital evolution.
Tidal evolution of the planet's orbit deposits energy into the planet's
interior resulting in an enlarged radius. Some previous calculations of
hot Jupiter tidal evolution have ignored the change in radius of the
planet, which we explicitly include here. We also investigate the future
evolution of the planet and find that it may end with the planet tidally
evolving into the Roche lobe of the host star and being destroyed. Our
study provides constraints on the past evolution of the planet and on
the present orbital and tidal parameters that can explain its current
radius.
Title: The Solar Eruption of 2005 May 13 and Its Effects:
Long-Baseline Interplanetary Scintillation
Observations of the Earth-Directed Coronal Mass
Ejection
Authors: Breen, A. R.; Fallows, R. A.; Bisi, M. M.;
Jones, R. A.; Jackson, B. V.; Kojima, M.;
Dorrian, G. D.; Middleton, H. R.; Thomasson, P.;
Wannberg, G.
Affiliation: AA(Institute of Mathematics and Physics, Aberystwyth
University, Penglais Hill, Aberystwyth, Ceredigion
of Mathematics and Physics, Aberystwyth University,
Penglais Hill, Aberystwyth, Ceredigion SY23 3BZ,
for Astrophysics and Space Science, University of
California, San Diego, 9500 Gilman Drive, La Jolla,
AD(Formerly at the Institute of Mathematics and
Physics, Aberystwyth University, Aberystwyth, Wales;
Astrophysics and Space Science, University of
California, San Diego, 9500 Gilman Drive, La Jolla,
AF(Solar-Terrestrial Environment Laboratory,
University of Nagoya, Furo-cho, Chikusa-ku, Nagoya
AG(Institute of Mathematics and Physics, Aberystwyth
University, Penglais Hill, Aberystwyth, Ceredigion
of Mathematics and Physics, Aberystwyth University,
Penglais Hill, Aberystwyth, Ceredigion SY23 3BZ,
Bank Observatory, University of Manchester, Jodrell
Bank, Macclesfield, Cheshire SK11 9DL, England;
Association, P.O. Box 164, Kiruna SE-981 23, Sweden;
Publication: The Astrophysical Journal, Volume 683, Issue 1, pp.
L79-L82.
Publication Date: 08/2008
Origin: UCP
ApJ Keywords: Scattering, Sun: Solar-terrestrial Relations, Sun:
Solar Wind, Sun: Coronal Mass Ejections (CMEs)
DOI: 10.1086/591520
Bibliographic Code: 2008ApJ...683L..79B
Abstract
Long-baseline observations of interplanetary scintillation (IPS) provide
a unique source of information on solar wind speed and meridional
direction across the inner regions of the solar system. We report the
results of a series of coordinated IPS observations of an Earth-directed
CME. A significant development in the interpretation of these data is
the use of 3D tomographic reconstructions of solar wind structure
derived from STELab IPS data to better constrain the analysis of
extremely long baseline observations from EISCAT and MERLIN. The
combination of these two approaches leads to a significantly better
understanding of the interaction of the CME with the background solar
wind than would be possible with either technique alone, revealing a
significant rotation in the meridional flow direction of the background
wind associated with the passage of the CME. The CME itself is
decelerated significantly between its emergence through the corona and
its arrival in the IPS ray path, with comparatively little change in
speed from then until arrival at ACE.
Title: ESPRIT: a study concept for a far-infrared
interferometer in space
Authors: Wild, W.; de Graauw, Th.; Helmich, F.; Baryshev, A.;
Cernicharo, J.; Gao, J. R.; Gunst, A.; Bos, A.;
den Herder, J.-W.; Jackson, B.; Koshelets, V.;
Langevelde, H.-J.; Maat, P.; Martin-Pintado, J.;
Noordam, J.; Roelfsema, P.; Venema, L.;
Wesselius, P.; Yagoubov, P.
Affiliation: AA(SRON Netherlands Institute for Space Research
(Netherlands) and Kapteyn Astronomical Institute,
Univ. of Groningen (Netherlands)), AB(SRON
Netherlands Institute for Space Research
(Netherlands) and Leiden Observatory (Netherlands)),
AC(SRON Netherlands Institute for Space Research
(Netherlands) and Kapteyn Astronomical Institute,
Univ. of Groningen (Netherlands)), AD(SRON
Netherlands Institute for Space Research
(Netherlands) and Kapteyn Astronomical Institute,
Univ. of Groningen (Netherlands)), AE(Consejo
Superior de Investigaciones Científicas (Spain)),
AF(SRON Netherlands Institute for Space Research
(Netherlands)), AG(ASTRON, Dwingeloo (Netherlands)),
AH(ASTRON, Dwingeloo (Netherlands)), AI(SRON
Netherlands Institute for Space Research
(Netherlands)), AJ(SRON Netherlands Institute for
Space Research (Netherlands)), AK(SRON Netherlands
Institute for Space Research (Netherlands) and
Institute of Radio Engineering and Electronics
(Russia)), AL(Joint Institute for VLBI in Europe
(Netherlands)), AM(ASTRON, Dwingeloo (Netherlands)),
AN(Consejo Superior de Investigaciones Científicas
(Spain)), AO(ASTRON, Dwingeloo (Netherlands)),
AP(SRON Netherlands Institute for Space Research
(Netherlands) and Kapteyn Astronomical Institute,
Univ. of Groningen, (Netherlands)), AQ(ASTRON,
Dwingeloo (Netherlands)), AR(SRON Netherlands
Institute for Space Research (Netherlands) and
Kapteyn Astronomical Institute, Univ. of Groningen
(Netherlands)), AS(SRON Netherlands Institute for
Space Research (Netherlands))
Publication: Optical and Infrared Interferometry. Edited by
Schöller, Markus; Danchi, William C.; Delplancke,
Françoise. Proceedings of the SPIE, Volume 7013,
pp. 70132R-70132R-10 (2008).
Publication Date: 07/2008
Origin: SPIE
DOI: 10.1117/12.789603
Bibliographic Code: 2008SPIE.7013E..84W
Abstract
In the far-infrared (FIR) / THz regime the angular (and often spectral)
resolution of observing facilities is still very restricted despite the
fact that this frequency range has become of prime importance for modern
astrophysics. ALMA (Atacama Large Millimeter Array) with its superb
sensitivity and angular resolution will only cover frequencies up to
about 1 THz, while the HIFI instrument for ESA'a Herschel Space
Observatory will provide limited angular resolution (10 to 30 arcsec) up
to 2 THz. Observations of regions with star and planet formation require
extremely high angular resolution as well as frequency resolution in the
full THz regime. In order to open these regions for high-resolution
astrophysics we present a study concept for a heterodyne space
interferometer, ESPRIT (Exploratory Submm Space Radio-Interferometric
Telescope). This mission will cover the Terahertz regime inaccessible
from the ground and outside the operating range of the James Webb Space
Telescope (JWST).
Title: Tidal Heating of Extrasolar Planets
Authors: Jackson, Brian; Greenberg, Richard; Barnes, Rory
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona, Tucson, AZ 85721), AB(Lunar and Planetary
Laboratory, University of Arizona, Tucson, AZ
85721), AC(Lunar and Planetary Laboratory,
University of Arizona, Tucson, AZ 85721)
Publication: The Astrophysical Journal, Volume 681, Issue 2, pp.
1631-1638.
Publication Date: 07/2008
Origin: UCP
ApJ Keywords: Celestial Mechanics
DOI: 10.1086/587641
Bibliographic Code: 2008ApJ...681.1631J
Abstract
Extrasolar planets close to their host stars have likely undergone
significant tidal evolution since the time of their formation. Tides
probably dominated their orbital evolution once the dust and gas cleared
away, and as the orbits evolved there was substantial tidal heating
within the planets. The tidal heating history of each planet may have
contributed significantly to the thermal budget governing the planet's
physical properties, including its radius, which in many cases may be
measured by observing transit events. Typically, tidal heating increases
as a planet moves inward toward its star and then decreases as its orbit
circularizes. Here we compute the plausible heating histories for
several planets with measured radii, using the same tidal parameters for
the star and planet that have been shown to reconcile the eccentricity
distribution of close-in planets with other extrasolar planets. Several
planets are discussed, including, for example, HD 209458b, which may
have undergone substantial tidal heating during the past billion years,
perhaps enough to explain its large measured radius. Our models also
show that GJ 876d may have experienced tremendous heating and is
probably not a solid, rocky planet. Theoretical models should include
the role of tidal heating, which is large but time-varying.
Title: Tides and the Evolution of Planetary Habitability
Authors: Barnes, Rory; Raymond, Sean N.; Jackson, Brian;
Greenberg, Richard
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona, Tucson, Arizona), AB(NASA Postdoctoral
Program Fellow. Center for Astrophysics and Space
Astronomy, University of Colorado, Boulder,
Colorado), AC(Lunar and Planetary Laboratory,
University of Arizona, Tucson, Arizona), AD(Lunar
and Planetary Laboratory, University of Arizona,
Tucson, Arizona)
Publication: Astrobiology, Volume 8, Issue 3, pp. 557-568.
Publication Date: 06/2008
Origin: ASBIO
Keywords: Extrasolar terrestrial planets, Habitable zones, M
stars, Gl 581,
DOI: 10.1089/ast.2007.0204
Bibliographic Code: 2008AsBio...8..557B
Abstract
Tides raised on a planet by the gravity of its host star can reduce the
planet's orbital semi-major axis and eccentricity. This effect is only
relevant for planets orbiting very close to their host stars. The
habitable zones of low-mass stars are also close in, and tides can alter
the orbits of planets in these locations. We calculate the tidal
evolution of hypothetical terrestrial planets around low-mass stars and
show that tides can evolve planets past the inner edge of the habitable
zone, sometimes in less than 1 billion years. This migration requires
large eccentricities (>0.5) and low-mass stars (≲0.35
Mo). Such migration may have important implications for
the evolution of the atmosphere, internal heating, and the Gaia
hypothesis. Similarly, a planet that is detected interior to the
habitable zone could have been habitable in the past. We consider the
past habitability of the recently discovered, ˜5
M⊕ planet, Gliese 581 c. We find that it could have
been habitable for reasonable choices of orbital and physical properties
as recently as 2 Gyr ago. However, when constraints derived from the
additional companions are included, most parameter choices that indicate
past habitability require the two inner planets of the system to have
crossed their mutual 3:1 mean motion resonance. As this crossing would
likely have resulted in resonance capture, which is not observed, we
conclude that Gl 581 c was probably never habitable.
Title: Zero-free regions for multivariate Tutte polynomials
(alias Potts-model partition functions) of graphs
and matroids
Authors: Jackson, Bill; Sokal, Alan D.
Publication: eprint arXiv:0806.3249
Publication Date: 06/2008
Origin: ARXIV
Keywords: Mathematics - Combinatorics, Mathematical Physics,
05C15 (Primary), 05A20, 05B35, 05C99, 05E99, 82B20
(Secondary)
Comment: LaTeX2e, 49 pages, includes 5 Postscript figures; J.
Combin. Theory B 99, 869--903 (2009);
doi:10.1016/j.jctb.2009.03.002
Bibliographic Code: 2008arXiv0806.3249J
Abstract
The chromatic polynomial P_G(q) of a loopless graph G is known to be
nonzero (with explicitly known sign) on the intervals (-\infty,0), (0,1)
and (1,32/27]. Analogous theorems hold for the flow polynomial of
bridgeless graphs and for the characteristic polynomial of loopless
matroids. Here we exhibit all these results as special cases of more
general theorems on real zero-free regions of the multivariate Tutte
polynomial Z_G(q,v). The proofs are quite simple, and employ
deletion-contraction together with parallel and series reduction. In
particular, they shed light on the origin of the curious number 32/27.
Title: Tidal evolution of close-in extra-solar planets
Authors: Jackson, Brian; Greenberg, Richard; Barnes, Rory
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona, 1629 E University Blvd Tucson, Arizona
and Planetary Laboratory, University of Arizona,
1629 E University Blvd Tucson, Arizona 85721-0092
USA), AC(Lunar and Planetary Laboratory, University
of Arizona, 1629 E University Blvd Tucson, Arizona
85721-0092 USA)
Publication: Exoplanets: Detection, Formation and Dynamics,
Proceedings of the International Astronomical Union,
IAU Symposium, Volume 249, p. 187-196
Publication Date: 05/2008
Origin: CUP
Keywords: celestial mechanics, planetary systems: formation,
protoplanetary disks
DOI: 10.1017/S1743921308016591
Bibliographic Code: 2008IAUS..249..187J
Abstract
The distribution of eccentricities e of extra-solar planets with
semi-major axes a > 0.2 AU is very uniform, and values for e are
generally large. For a < 0.2 AU, eccentricities are much smaller
(most e < 0.2), a characteristic widely attributed to damping by
tides after the planets formed and the protoplanetary gas disk
dissipated. We have integrated the classical coupled tidal evolution
equations for e and a backward in time over the estimated age of each
planet, and confirmed that the distribution of initial e values of
close-in planets matches that of the general population for reasonable
tidal dissipation values Q, with the best fits for stellar and planetary
Q being 105.5 and 106.5, respectively. The
current small values of a were only reached gradually due to tides over
the lifetimes of the planets, i.e., the earlier gas disk migration did
not bring all planets to their current orbits. As the orbits tidally
evolved, there was substantial tidal heating within the planets. The
past tidal heating of each planet may have contributed significantly to
the thermal budget that governed the planet's physical properties,
including its radius, which in many cases may be measured by observing
transit events. Here we also compute the plausible heating histories for
a few planets with anomalously large measured radii, including HD 209458
b. We show that they may have undergone substantial tidal heating during
the past billion years, perhaps enough to explain their large radii.
Theoretical models of exoplanet interiors and the corresponding radii
should include the role of large and time-variable tidal heating. Our
results may have important implications for planet formation models,
physical models of ``hot Jupiters'', and the success of
transit surveys.
Title: Tidal Evolution of Close-in Extrasolar Planets
Authors: Jackson, Brian; Greenberg, Richard; Barnes, Rory
Affiliation: AA(Lunar and Planetary Laboratory, University of
Arizona, 1629 East University Boulevard, Tucson, AZ
85721-0092), AB(Lunar and Planetary Laboratory,
University of Arizona, 1629 East University
Boulevard, Tucson, AZ 85721-0092), AC(Lunar and
Planetary Laboratory, University of Arizona, 1629
East University Boulevard, Tucson, AZ 85721-0092)
Publication: The Astrophysical Journal, Volume 678, Issue 2, pp.
1396-1406.
Publication Date: 05/2008
Origin: UCP
ApJ Keywords: Celestial Mechanics, Stars: Planetary Systems:
Formation, Stars: Planetary Systems: Protoplanetary
Disks
DOI: 10.1086/529187
Bibliographic Code: 2008ApJ...678.1396J
Abstract
The distribution of eccentricities e of extrasolar planets with
semimajor axes a>0.2 AU is very uniform, and values for e are
relatively large, averaging 0.3 and broadly distributed up to near 1.
For a<0.2 AU, eccentricities are much smaller (most e<0.2), a
characteristic widely attributed to damping by tides after the planets
formed and the protoplanetary gas disk dissipated. Most previous
estimates of the tidal damping considered the tides raised on the
planets, but ignored the tides raised on the stars. Most also assumed
specific values for the planets' poorly constrained tidal dissipation
parameter Qp. Perhaps most important, in many studies the
strongly coupled evolution between e and a was ignored. We have now
integrated the coupled tidal evolution equations for e and a over the
estimated age of each planet, and confirmed that the distribution of
initial e values of close-in planets matches that of the general
population for reasonable Q values, with the best fits for stellar and
planetary Q being ~105.5 and ~106.5, respectively.
The accompanying evolution of a values shows most close-in planets had
significantly larger a at the start of tidal migration. The earlier gas
disk migration did not bring all planets to their current orbits. The
current small values of a were only reached gradually due to tides over
the lifetimes of the planets. These results may have important
implications for planet formation models, atmospheric models of ``hot
Jupiters,'' and the success of transit surveys.
Title: SMEI Observations of the Heliosphere During WHI
Authors: Jackson, B. V.; Bisi, M. M.; Hick, P. P.;
Buffington, A.; Clover, J. M.; Webb, D. F.
Affiliation: AA(Center for Astrophysics and Space Sciences, La
Jolla, CA, La Jolla, CA 92093, United States;
and Space Sciences, La Jolla, CA, La Jolla, CA
for Astrophysics and Space Sciences, La Jolla, CA,
La Jolla, CA 92093, United States;
Space Sciences, La Jolla, CA, La Jolla, CA 92093,
for Astrophysics and Space Sciences, La Jolla, CA,
La Jolla, CA 92093, United States;
Chestnut Hill, MA, Chestnut Hill, MA, United States
Publication: American Geophysical Union, Spring Meeting 2008,
abstract \#SH51A-08
Publication Date: 05/2008
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 2102 Corotating
streams, 2111 Ejecta, driver gases, and magnetic
clouds, 7513 Coronal mass ejections (2101), 7833
Mathematical and numerical techniques (0500, 3200)
Bibliographic Code: 2008AGUSMSH51A..08J
Abstract
Solar Mass Ejection Imager (SMEI) observations of the inner heliosphere
have been carried out on a routine basis since early 2003. By employing
a kinematic model of the solar wind, we reconstruct three-dimensional
(3D) solar wind structures from multiple observing lines of sight
through the outward-flowing solar wind. These models allow us to
extract solar wind density and to compare these to "ground truth"
measurements from multi- point in-situ solar wind measurements from the
STEREO, SOHO, ACE, and the Wind spacecraft. This aids in improving the
3D reconstruction technique by comparing these reconstructions at
multiple points in the inner heliosphere. Because our observations
reveal the global nature of heliospheric structures, this also leads to
a better understanding of the structure and dynamics of the
interplanetary environment around each spacecraft, and how these
structures are connected back to the Sun. During the Whole Heliosphere
Interval (WHI) SMEI will provide views and 3D reconstructions of the
global heliosphere that can be compared with ground-based and spacecraft
observations.
Title: Observations of a comet tail disruption induced by
the passage of a CME
Authors: Kuchar, T. A.; Buffington, A.; Arge, C. N.;
Hick, P. P.; Howard, T. A.; Jackson, B. V.;
Johnston, J. C.; Mizuno, D. R.; Tappin, S. J.;
Webb, D. F.
Affiliation: AA(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA);
AB(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AC(Air Force Research Laboratory,
Space Vehicles Directorate, Hanscom AFB,
Massachusetts, USA); AD(Center for Astrophysics and
Space Sciences, University of California, San Diego,
La Jolla, California, USA); AE(Physics Department,
Montana State University, Bozeman, Montana, USA);
AF(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AG(Air Force Research Laboratory,
Space Vehicles Directorate, Hanscom AFB,
Massachusetts, USA); AH(Institute for Scientific
Research, Boston College, Chestnut Hill,
Massachusetts, USA); AI(National Solar
Observatory/Sacramento Peak, Sunspot, New Mexico,
USA); AJ(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA)
Publication: Journal of Geophysical Research, Volume 113, Issue
A4, CiteID A04101
Publication Date: 04/2008
Origin: AGU
AGU Keywords: Planetary Sciences: Comets and Small Bodies: Comets:
dust tails and trails (6210), Planetary Sciences:
Solar System Objects: Comets (6023), Interplanetary
Physics: Coronal mass ejections (7513),
Interplanetary Physics: Heliosphere/interstellar
medium interactions
DOI: 10.1029/2007JA012603
Bibliographic Code: 2008JGRA..11304101K
Abstract
The Solar Mass Ejection Imager observed an extremely faint
interplanetary coronal mass ejection (ICME) as it passed Comet C/2001 Q4
(NEAT) on 5 May 2004, apparently causing a disruption of its plasma
tail. This is the first time that an ICME has been directly observed
interacting with a comet. SMEI's nearly all-sky coverage and image
cadence afforded unprecedented coverage of this rarely observed event.
The onset first appeared as a ``kink'' moving antisunward that
eventually developed knots within the disturbed tail. These knots
appeared to be swept up in the solar wind flow. We present the SMEI
observations as well as identify a likely SOHO/LASCO progenitor of the
CME. SMEI observed two other comets (C/2002 T7 [LINEAR] and C/2004 F4
[Bradfield]) and at least five similar events during a 35-d period
encompassing this observation. Although these had similar morphologies
to the 5 May NEAT event, SMEI did not observe any ICMEs in these cases.
Three of these were observed close to the heliospheric current sheet
indicating that a magnetic boundary crossing may have contributed to the
disruptions. However, there are no discernable causes in the SMEI
observations for the remaining two events.
Title: Numerical Simulations of Solar Wind Disturbances by
Coupled Models
Authors: Odstrcil, D.; Pizzo, V. J.; Arge, C. N.;
Bissi, M. M.; Hick, P. P.; Jackson, B. V.;
Ledvina, S. A.; Luhmann, J. G.; Linker, J. A.;
Mikic, Z.; Riley, P.
Publication: Numerical Modeling of Space Plasma Flows: Astronum
2007 ASP Conference Series, Vol. 385, proceedings of
the conference held 10-15 June, 2007, at Hotel
Concorde Montparnasse, Paris, France. Edited by
Nikolai V. Pogorelov, Edouard Audit, and Gary P.
Zank. San Francisco: Astronomical Society of the
Pacific, 2008., p.167
Publication Date: 04/2008
Origin: ASP
Bibliographic Code: 2008ASPC..385..167O
Abstract
Numerical modeling plays a critical role in efforts to understand the
connection between solar eruptive phenomena and their impacts in the
near-Earth space environment and in interplanetary space. Coupling the
heliospheric model with empirical, observational, and numerical coronal
models is described. Results show background solar wind, evolution of
interplanetary transients, connectivity of magnetic field lines, and
interplanetary shocks approaching geospace.
Title: Quantification of atmospheric seeing conditions
while conducting observations in Ursa Major.
Authors: Clifford, Joshua; Jackson, Brittany; Jones, Adam
Publication: American Physical Society, 2008 APS April Meeting
and HEDP/HEDLA Meeting, April 11-15, 2008, abstract
\#S1.047
Publication Date: 04/2008
Origin: APS
Bibliographic Code: 2008APS..APR.S1047C
Abstract
Researchers from Telescopes in Education and Research at Murray State
(TERMS) recently developed indices to quantify astronomical seeing
conditions. The required images were converted from a consumer grade
VHS-C camcorder video by USB powered TV tuner into an uncompressed AVI
format and imported into Image J for analysis. The first analysis was
for HIP 26241, also known as Iota Orionis. We reproduce the technique
for a different region of the sky around HIP 65378, also known as Mizar,
at a different time of year from the same urban environment. For the
star in question, we determine the photometric index and measure the
horizontal and vertical drift from frame to frame of the uncompressed
AVI file to quantify the ``jitter'' observed in the video. Our results
and the previous results for Iota Orionis with regard to photometric
index and ``jitter'' will be compared.
Title: Analysis of Plasma-Tail Motions for Comets C/2001 Q4
(NEAT) and C/2002 T7 (LINEAR) Using Observations
from SMEI
Authors: Buffington, A.; Bisi, M. M.; Clover, J. M.;
Hick, P. P.; Jackson, B. V.; Kuchar, T. A.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093-0424
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093-0424
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093-0424
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093-0424
Research Boston College Chestnut Hill, MA 02147;
Publication: The Astrophysical Journal, Volume 677, Issue 1, pp.
798-807.
Publication Date: 04/2008
Origin: UCP
ApJ Keywords: comets: individual (C/2001 Q4 (NEAT)), Comets:
Individual: Alphanumeric: C/2002 T7 (LINEAR),
comets: individual (C/2004 F4 (Bradfield)), Sun:
Solar Wind, Sun: Coronal Mass Ejections (CMEs)
DOI: 10.1086/529039
Bibliographic Code: 2008ApJ...677..798B
Abstract
Comets C/2001 Q4 (NEAT) and C/2002 T7 (LINEAR) passed within ~0.3 AU of
Earth in April and May of 2004. Their tails were observed by the
Earth-orbiting Solar Mass Ejection Imager (SMEI) during this period. A
time series of photometric SMEI sky maps displays the motions and
frequent disruptions of the comet plasma tails. Ephemerides are used to
unfold the observing geometry; the tails are often seen to extend ~0.5
AU from the comet nuclei. Having selected 12 of the more prominent
motions as ``events'' for further study, we introduce a new method for
determining solar wind radial velocities from these SMEI observations.
We find little correlation between these and the changing solar wind
parameters as measured close to Earth, or with coarse three-dimensional
reconstructions using interplanetary scintillation data. A likely
explanation is that the transverse sizes of the solar wind perturbations
responsible for these disruptions are small, <~0.05 AU. We determine
the radial velocities of these events during the disruptions, using a
technique only possible when the observed comet tails extend over a
significant fraction of an AU. We find typical radial velocities during
these events of 50-100 km s-1 lower than before or afterward.
Time durations of such events vary, typically from 3 to 8 hr, and
correspond to comet traversal distances ~106 km (0.007 AU).
We conclude that these large disturbances are primarily due to
ubiquitous solar wind flow variations, of which these measured events
are a subset.
Title: Quantum studies of light particle trapping,
sticking, and desorption on metal and graphite
surfaces
Authors: Medina, Zuleika; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA
Publication: Journal of Chemical Physics, Volume 128, Issue 11,
pp. 114704-114704-9 (2008).
Publication Date: 03/2008
Origin: AIP
Keywords: adsorption, atom-surface impact, copper, desorption,
graphite, helium, hydrogen
Abstract Copyright: (c) 2008: American Institute of Physics
DOI: 10.1063/1.2890043
Bibliographic Code: 2008JChPh.128k4704M
Abstract
A quantum mechanical formalism capable of describing the scattering,
trapping, sticking, and desorption of an atom from a moving corrugated
surface is presented. While the instantaneous particle-bath interaction
is assumed to be weak, the particle and the bath can exchange energy
over long periods of time. We have explored the trapping desorption and
trapping-relaxation-sticking of He on Cu(110) and of H on
graphite(0001). Higher substrate temperatures generally lead to
increased trapping, but a higher desorption rate eventually leads to
less, or zero sticking, at long times. In both cases, we observe that
trapping in diffraction-mediated selective adsorption resonances can
enhance sticking at low incident energies. While trapped in the
resonance, the atom can relax toward the ground state of the
gas-substrate attractive well. If the binding energy is larger than the
amount of energy in the atom's motion parallel to the surface, it
remains stuck at long times, at sufficiently low temperatures. We find
sticking probabilities on the order of 1% at very low energies for both
systems. In the vicinity of a selective adsorption resonance, this
sticking can increase by several percent, depending on the size of the
corrugation.
Title: A fundamental avian wing-stroke provides a new
perspective on the evolution of flight
Authors: Dial, Kenneth P.; Jackson, Brandon E.; Segre, Paolo
Affiliation: AA(Flight Laboratory, Division of Biological
Sciences, University of Montana, 32 Campus Drive,
Missoula, Montana 59812, USA), AB(Flight Laboratory,
Division of Biological Sciences, University of
Montana, 32 Campus Drive, Missoula, Montana 59812,
USA), AC(Flight Laboratory, Division of Biological
Sciences, University of Montana, 32 Campus Drive,
Missoula, Montana 59812, USA)
Publication: Nature, Volume 451, Issue 7181, pp. 985-989 (2008).
Publication Date: 02/2008
Origin: NATURE
Abstract Copyright: (c) 2008: Nature
DOI: 10.1038/nature06517
Bibliographic Code: 2008Natur.451..985D
Abstract
The evolution of avian flight remains one of biology's major
controversies, with a long history of functional interpretations of
fossil forms given as evidence for either an arboreal or cursorial
origin of flight. Despite repeated emphasis on the `wing-stroke' as a
necessary avenue of investigation for addressing the evolution of
flight, no empirical data exist on wing-stroke dynamics in an
experimental evolutionary context. Here we present the first comparison
of wing-stroke kinematics of the primary locomotor modes (descending
flight and incline flap-running) that lead to level-flapping flight in
juvenile ground birds throughout development (Fig. 1). We offer results
that are contrary both to popular perception and inferences from other
studies. Starting shortly after hatching and continuing through
adulthood, ground birds use a wing-stroke confined to a narrow range of
less than 20°, when referenced to gravity, that directs aerodynamic
forces about 40° above horizontal, permitting a 180° range in
the direction of travel. Based on our results, we put forth an
ontogenetic-transitional wing hypothesis that posits that the
incremental adaptive stages leading to the evolution of avian flight
correspond behaviourally and morphologically to transitional stages
observed in ontogenetic forms.
Title: The sticking of H and D atoms on a graphite (0001)
surface: The effects of coverage and energy
dissipation
Authors: Kerwin, Jay; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA
Publication: Journal of Chemical Physics, Volume 128, Issue 8,
pp. 084702-084702-7 (2008).
Publication Date: 02/2008
Origin: AIP
Keywords: adsorption, carbon, chemisorption, density
functional theory, deuterium, hydrogen, total
energy, vibrational modes
Abstract Copyright: (c) 2008: American Institute of Physics
DOI: 10.1063/1.2868771
Bibliographic Code: 2008JChPh.128h4702K
Abstract
Classical trajectory methods are used to examine the trapping and
sticking of H and D atoms on the graphite (0001) surface. Total energy
calculations based on density functional theory are used to construct
the model potential energy surface, and graphite clusters of up to 121
atoms are considered. For hydrogen to chemisorb, the bonding carbon must
pucker out of the surface plane by roughly 0.4 A˚. For incident
energies above the 0.2 eV barrier, any trapped H atoms must rapidly
dissipate their excess energy into the surrounding lattice within a few
vibrations of the C-H stretch in order to remain bound. For sufficiently
large clusters, the C-H bond stabilizes within about 0.1 ps. The
sticking probability for D at 150 K is in the range of 5%-10%,
more-or-less consistent with the most recent measurements in the limit
of zero coverge. Variation with isotope and substrate temperature is
weak. We estimate that the sticking cross section for adsorption at the
para site, directly across the sixfold carbon ring from an already
adsorbed H atom, can be four or more times larger that the zero coverage
sticking cross section.
Title: Methane dissociation on Ni(111): The effects of
lattice motion and relaxation on reactivity
Authors: Nave, Sven; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003
Publication: Journal of Chemical Physics, Volume 127, Issue 22,
pp. 224702-224702-11 (2007).
Publication Date: 12/2007
Origin: AIP
Keywords: adsorption, density functional theory, dissociation,
lattice dynamics, nickel, organic compounds,
potential energy surfaces, reaction kinetics,
scattering, vibrational modes
Abstract Copyright: (c) 2007: American Institute of Physics
DOI: 10.1063/1.2800661
Bibliographic Code: 2007JChPh.127v4702N
Abstract
The effects of lattice motion and relaxation on the dissociative
adsorption of methane on a Ni(111) surface are explored. Electronic
structure methods based on the density functional theory are used to
compute the potential energy surface for this reaction. It is found
that, in the transition state and product regions, there are forces
causing the Ni atom over which the molecule dissociates to move out of
the surface. In order to examine the extent to which the lattice might
pucker during this reaction, high dimensional fully quantum scattering
calculations are carried out. It is found that a significant amount of
lattice puckering can occur, even at large collision energies, lowering
the barrier to reaction and increasing the dissociative sticking
probability. This is shown to be in contrast to the predictions of the
surface oscillator model. While we observe similar puckering forces for
this reaction on Pt(111), our calculations suggest that the puckering on
this surface will be considerably less due to the larger metal atom
mass. The ``laser off'' reactivities of CD3H on Ni(111) are
computed, and it is demonstrated that there can be significant
contributions to the reactivity from vibrationally excited molecules,
particularly at lower collision energies, or when a large nozzle
temperature is required to attain the necessary collision energy for
reaction. Comparisons are made with recent experiments with regard to
the variation of reactivity with collision energy, vibrational state,
and surface temperature.
Title: Inner-heliosphere SMEI observations and their
comparison with multi-point in-situ measurements
Authors: Jackson, B. V.; Bisi, M. M.; Hick, P. P.;
Buffington, A.; Clover, J. M.; Feynman, J.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, United States
and Space Sciences, University of California, San
Diego, 9500 Gilman Drive \#0424, La Jolla, CA
AC(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, United States
Space Sciences, University of California, San Diego,
9500 Gilman Drive \#0424, La Jolla, CA 92093-0424,
for Astrophysics and Space Sciences, University of
California, San Diego, 9500 Gilman Drive \#0424, La
Jolla, CA 92093-0424, United States;
M/8 169-506 4800 Oak Grove Dr., Pasadena, CA 91109,
Publication: American Geophysical Union, Fall Meeting 2007,
abstract \#SH51B-03
Publication Date: 12/2007
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 6969 Remote
sensing, 7513 Coronal mass ejections (2101), 7599
General or miscellaneous, 7899 General or
miscellaneous
Bibliographic Code: 2007AGUFMSH51B..03J
Abstract
Solar Mass Ejection Imager (SMEI) observations of the inner heliosphere
have been carried out on a routine basis since shortly after its launch
on January 6, 2003. By employing a kinematic model of the solar wind,
we reconstruct three-dimensional (3D) solar wind structures from
multiple observing lines of sight through the outward-flowing solar
wind. This model allows us to extract solar wind densities from the
SMEI white-light observations and to compare these to multi-point in
situ "ground truth" solar wind measurements from instruments aboard the
Ulysses, STEREO, ACE, and Wind spacecraft. This facilitates
improvements to our 3D reconstruction technique by comparing these
reconstructions at multiple points in the inner-heliosphere. Our
observations show heliospheric structures globally, and because of this,
our reconstructions provide us with a better understanding of the
structure and dynamics of the interplanetary environment around each
spacecraft, and how these structures are connected back to the Sun.
Title: IPS observations of the inner-heliosphere and their
comparison with multi-point in-situ measurements
Authors: Bisi, M. M.; Jackson, B. V.; Breen, A. R.;
Fallows, R. A.; Feynman, J.; Clover, J. M.;
Hick, P. P.; Buffington, A.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, United States
Space Sciences, University of California, San Diego,
9500 Gilman Drive \#0424, La Jolla, CA 92093-0424,
of Mathematical and Physical Sciences, University of
Wales, Aberystwyth, Penglais Campus, Aberystwyth,
AD(Institute of Mathematical and Physical Sciences,
University of Wales, Aberystwyth, Penglais Campus,
Aberystwyth, SY23 3BZ, United Kingdom;
169-506 4800 Oak Grove Drive, Pasadena, CA 91109,
AF(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, United States
and Space Sciences, University of California, San
Diego, 9500 Gilman Drive \#0424, La Jolla, CA
AH(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, United States
Publication: American Geophysical Union, Fall Meeting 2007,
abstract \#SH33A-1091
Publication Date: 12/2007
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 6969 Remote
sensing, 7513 Coronal mass ejections (2101), 7599
General or miscellaneous, 7899 General or
miscellaneous
Bibliographic Code: 2007AGUFMSH33A1091B
Abstract
Interplanetary scintillation (IPS) observations of the inner-heliosphere
have been carried out on a routine basis for many years using
metre-wavelength radio telescope arrays. By employing a kinematic model
of the solar wind, we reconstruct the three-dimensional (3D) structure
of the inner-heliosphere from multiple observing lines of sight. From
these reconstructions we extract solar wind parameters such as velocity
and density, and compare these to "ground truth" measurements from
multi-point in situ solar wind measurements from ACE, Ulysses, STEREO,
and the Wind spacecraft, particularly during the International
Heliophysical Year (IHY). These multi- point comparisons help us
improve our 3D reconstruction technique. Because our observations show
heliospheric structures globally, this leads to a better understanding
of the structure and dynamics of the interplanetary environment around
these spacecraft.
Title: Analysis and Interpretation of Comet Measurements
from SMEI
Authors: Buffington, A.; Bisi, M. M.; Clover, J. M.;
Hick, P. P.; Jackson, B. V.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, 9500 Gilman
Drive \#0424, La Jolla, CA 92093-0424, United States
Astrophysics and Space Sciences, University of
California, San Diego, 9500 Gilman Drive \#0424, La
Jolla, CA 92093-0424, United States;
Space Sciences, University of California, San Diego,
9500 Gilman Drive \#0424, La Jolla, CA 92093-0424,
Astrophysics and Space Sciences, University of
California, San Diego, 9500 Gilman Drive \#0424, La
Jolla, CA 92093-0424, United States;
Space Sciences, University of California, San Diego,
9500 Gilman Drive \#0424, La Jolla, CA 92093-0424,
Publication: American Geophysical Union, Fall Meeting 2007,
abstract \#SH33A-1080
Publication Date: 12/2007
Origin: AGU
AGU Keywords: 2199 General or miscellaneous, 6025 Interactions
with solar wind plasma and fields, 6099 General or
miscellaneous, 6210 Comets (6023), 7594 Instruments
and techniques
Bibliographic Code: 2007AGUFMSH33A1080B
Abstract
The Solar Mass Ejection Imager (SMEI) has observed several comets and
traced their plasma tails as far as 108 km from their nucleus. A time
sequence of SMEI orbital sky maps displays considerable tail motion and
disruption for several of these comets. Tracking these motions versus
time, when combined with ephemeris information about their distance
from the Earth allows a determination of solar wind speeds and their
variation with the location of the comet. In the case of comets C/2001
Q4 (NEAT) and C/2002 T7 (LINEAR), which passed within about 0.3 AU of
Earth in April and May of 2004, the SMEI observations show that speeds
during disruptions are typically 50 to 100 km s-1 less than speeds
before and after. Time durations of the disturbances vary between 3 and
8 hours, and correspond to distances traversed by the comets of ~106 km
(0.007 AU). We compare these observations with interplanetary
scintillation (IPS) three-dimensional tomographic reconstructions and
find no evidence that the comet-tail features are due to large-scale
density or velocity structures. We also compare these with near-by
spacecraft measurements such as the Advanced Composition Explorer (ACE),
and find a similar result. This suggests that the comet-tail
disruptions are caused by small-scale changes in the solar wind acting
over distances that are short compared with 1 AU.
Title: Creating and Accessing the Global Fluxnet Data Set
Authors: Agarwal, D.; Baldocchi, D.; Boden, T.; Cook, B.;
Frank, D.; Goode, M.; Gupchup, J.; Holladay, S.;
Humphrey, M.; van Ingen, C.; Jackson, B.; Papale, D.;
Reichstein, M.; Rodrigu{\'{e}}z, M.; Ryu, Y.; Vargas, R.;
Wilson, B.; Li, N.
Affiliation: AA(Berkeley Water Center, LBNL/University of
California, Berkeley 1 Cyclotron Rd, MS 50B-2239,
Berkeley, CA 94720, United States;
Berkeley, 137 Mulford Hall Ecosystem Sciences
Division, Department of Environmental Science,
Policy and Management, Berkeley, CA 94720-3110,
AC(Oak Ridge National Laboratory, Environmental
Sciences Division, Oak Ridge, TN 37831- 4842, United
Laboratory, Environmental Sciences Division, Oak
Ridge, TN 37831- 4842, United States;
Ecology, Universitätsstraße 30, Bayreuth, D 95440,
Water Center, LBNL/University of California,
Berkeley 1 Cyclotron Rd, MS 50B-2239, Berkeley, CA
Hopkins University, Dept. of Computer Science, 3400
N. Charles Street, Baltimore, MD 21218, United
National Laboratory, Environmental Sciences
Division, Oak Ridge, TN 37831- 4842, United States;
School of Engineering and Applied Science Olsson
Hall 236C, 151 Engineer's Way, P.O. Box 400740,
Charlottesville, VA 22904, United States;
455 Market St., Suite 1690, San Francisco, CA 94105,
Ridge National Laboratory, Environmental Sciences
Division, Oak Ridge, TN 37831- 4842, United States;
della Tuscia, Via Camillo de Lellis, snc - 01100,
Viterbo, 01100, Italy;
AM(University of Bayreuth, Plant Ecology,
Universitätsstraße 30, Bayreuth, D 95440, Germany;
Water Center, LBNL/University of California,
Berkeley 1 Cyclotron Rd, MS 50B-2239, Berkeley, CA
AO(University of California, Berkeley, 137 Mulford
Hall Ecosystem Sciences Division, Department of
Environmental Science, Policy and Management,
Berkeley, CA 94720-3110, United States;
California, Berkeley, 137 Mulford Hall Ecosystem
Sciences Division, Department of Environmental
Science, Policy and Management, Berkeley, CA
94720-3110, United States;
National Laboratory, Environmental Sciences
Division, Oak Ridge, TN 37831- 4842, United States;
Department of Physics and Astronomy 3701 San Martin
Dr, Baltimore, MD 21218, United States;
Publication: American Geophysical Union, Fall Meeting 2007,
abstract \#B33E-1657
Publication Date: 12/2007
Origin: AGU
AGU Keywords: 0434 Data sets
Abstract Copyright: (c) 2007: American Geophysical Union
Bibliographic Code: 2007AGUFM.B33E1657A
Abstract
The recently gathered FLUXNET synthesis dataset contains on the order of
900 site years from over 260 sites. The size of this dataset makes
browsing of the data difficult for users without additional help. For
instance, a search of the dataset for sites with particular
meteorological or flux characteristics would require a download of the
complete dataset and then running all of the data through a preliminary
analysis. Instead we have developed a Scientific Data Server which
enables browsing of the data on-line and then download of only the data
needed for an analysis. The Scientific Data Server leverages modern
database technology and stores the data in a database. This server
allows individual researchers to concentrate on science rather than data
management. We leverage database tools such as data cubes and web
reports to enable Excel pivot table and browser access to the data. It
is our belief that by using these tools a researcher can quickly and
easily evaluate the quality and availability of the data and identify
sites able to support a specific analysis. In addition, we have
leveraged available collaboration technology to incorporate support for
contact between site PIs and researchers hoping to use their data. In
this talk we will give a brief introduction to the data server and its
available features.
Title: FLUXNET: Data from a Global Network of
Eddy-Covariance Flux Towers
Authors: Cook, R. B.; Holladay, S. K.; Santhana Vannan, S. K.;
Pan, J. Y.; Jackson, B. L.; Wilson, B. E.
Affiliation: AA(Environmental Sciences Division, Oak Ridge
National Laboratory, Oak Ridge, TN 37830, United
Sciences Division, Oak Ridge National Laboratory,
Oak Ridge, TN 37830, United States;
Division, Oak Ridge National Laboratory, Oak Ridge,
AD(Environmental Sciences Division, Oak Ridge
National Laboratory, Oak Ridge, TN 37830, United
Division, Oak Ridge National Laboratory, Oak Ridge,
AF(Environmental Sciences Division, Oak Ridge
National Laboratory, Oak Ridge, TN 37830, United
Publication: American Geophysical Union, Fall Meeting 2007,
abstract \#B33E-1656
Publication Date: 12/2007
Origin: AGU
AGU Keywords: 0414 Biogeochemical cycles, processes, and modeling
(0412, 0793, 1615, 4805, 4912), 0426
Biosphere/atmosphere interactions (0315), 0428
Carbon cycling (4806), 0430 Computational methods
and data processing, 0439 Ecosystems, structure and
dynamics (4815)
Abstract Copyright: (c) 2007: American Geophysical Union
Bibliographic Code: 2007AGUFM.B33E1656C
Abstract
FLUXNET is an internationally coordinated global network of long-term
micrometeorological flux measurement sites that focus on measuring and
interpreting the land-atmosphere exchanges of carbon dioxide, water
vapor, and energy. The FLUXNET Data and Information System compiles
flux data and related site characteristics data from regional flux
networks from around the world for modeling the carbon cycle, analyzing
the analysis of the controls on carbon, water, and energy fluxes, and
validating remote sensing products. Flux data are being used to
evaluate ecosystem model outputs and to validate remote sensing
products, such as the photosynthesis product derived from the MODIS
sensor on the Terra and Aqua satellites. Comparison of information from
multiple types of local and regional studies is needed for understanding
the dynamics of ecosystem-atmosphere carbon dioxide exchange and for
extrapolating site studies to larger-scale products derived from remote
sensing or global-scale modeling. We will demonstrate data products and
tools for facilitating acquisition and intercomparison of the flux data,
model output, and remote sensing data.
Title: Tidal Evolution of Close-in Extra-Solar Planets
Authors: Jackson, Brian; Barnes, R.; Greenberg, R.
Affiliation: AA(University of Arizona), AB(University of
Arizona), AC(University of Arizona)
Publication: American Astronomical Society, AAS Meeting \#211,
\#68.01; Bulletin of the American Astronomical
Society, Vol. 39, p.857
Publication Date: 12/2007
Origin: AAS
Bibliographic Code: 2007AAS...211.6801J
Abstract
Eccentricities e of extra-solar planets with semi-major axes a > 0.2
AU are large, averaging 0.24 and broadly distributed up to near 1. For
smaller a, eccentricities are much smaller (most < 0.2), which is
widely attributed to damping by tides after the planets formed and the
gaseous disk dissipated. Previous estimates of the damping rates
considered the tide raised on the planet by the star, but ignored the
tide raised on the star. Also, specific values were assumed for the
planet's poorly constrained tidal dissipation parameter Q. Perhaps most
important, the strongly coupled evolution between a and e was ignored.
We have now integrated the full coupled tidal evolution equations for e
and a over the estimated age of each planet, and confirm that the
distribution of initial e values of close-in planets can match that of
the general population. Eccentricity distributions are best matched for
stellar and planetary Q values of 1e5.5 and 1e6.5, respectively. The
accompanying coupled tidal evolution of a values (mutually dependent on
the evolution of e) was also significant: At the start of tidal
migration, all planets had a > 0.04 AU, typically > twice their
current values. It appears that gas disk migration did not bring planets
closer than 0.04 AU, and that the current smaller values of a were only
reached gradually due to tides over the lifetimes of the planets. For
many planets, we also find that the past tidal heating rate was probably
much larger than at present. For example, HD 209458 b may have
experienced orders of magnitude more tidal heating within the past <
1 Gyr, which might help explain its anomalously large radius. Models of
the early physical evolution of "hot Jupiters'' should include
tidal migration and account for the much larger tidal heating in the
past.
Title: Comparison of the extent and mass of CME events in
the interplanetary medium using IPS and SMEI Thomson
scattering observations
Authors: Jackson, B. V.; Hick, P. P.; Buffington, A.;
Bisi, M. M.; Kojima, M.; Tokumaru, M.
Publication: Astronomical & Astrophysical Transactions, vol. 26,
issue 6, pp. 477-487
Publication Date: 12/2007
Origin: CROSSREF
DOI: 10.1080/10556790701612221
Bibliographic Code: 2007A&AT...26..477J
Abstract
Not Available
Title: IPS tomographic observations of 3D solar wind
structure
Authors: Kojima, M.; Tokumaru, M.; Fujiki, K.; Hayashi, K.;
Jackson, B. V.
Publication: Astronomical & Astrophysical Transactions, vol. 26,
issue 6, pp. 467-476
Publication Date: 12/2007
Origin: CROSSREF
DOI: 10.1080/10556790701596200
Bibliographic Code: 2007A&AT...26..467K
Abstract
Not Available
Title: Tides and the Evolution of Planetary Habitability
Authors: Barnes, Rory; Raymond, S. N.; Jackson, B.;
Greenberg, R.
Affiliation: AA(Univ. of Arizona), AB(Univ. of Colorado),
AC(Univ. of Arizona), AD(Univ. of Arizona)
Publication: American Astronomical Society, DPS meeting \#39,
\#29.09; Bulletin of the American Astronomical
Society, Vol. 39, p.468
Publication Date: 10/2007
Origin: AAS
Bibliographic Code: 2007DPS....39.2909B
Abstract
Tides raised on a planet by its host star's gravity can reduce a
planet's orbital semi-major axis and eccentricity. This effect is only
relevant for planets orbiting very close to their host stars. The
habitable zones of low-mass stars are also close-in and tides can alter
the orbits of planets in these locations. We calculate the tidal
evolution of hypothetical terrestrial planets around low-mass stars and
show that tides can evolve planets past the inner edge of
the habitable zone, sometimes in less than 1 billion years. This
migration requires large eccentricities (>0.5) and low-mass stars
(<0.35 MSun). Such migration may have important
implications for the evolution of the atmosphere, as well as internal
heating. Similarly, a planet detected interior to the habitable zone
could have been habitable in the past. We consider the past habitability
of the recently-discovered, 5 MEarth planet, Gliese 581 c.
We find that it could have been
habitable for reasonable choices of orbital and physical properties as
recently as 2 Gyr ago. However, when we include constraints derived from
the additional companions, we see that most parameter choices that
predict past habitability require the two inner planets of the system to
have crossed their mutual 3:1 mean motion resonance. As this crossing
would likely have resulted in resonance capture, which is not observed,
we conclude that Gl 581 c was probably never habitable.
Title: Combined STELab, EISCAT, ESR, and MERLIN IPS
observations of the solar wind
Authors: Bisi, Mario M.; Jackson, Bernard V.;
Fallows, Richard A.; Breen, Andrew R.; Hick, P. Paul;
Wannberg, Gudmund; Thomasson, Peter;
Jordan, Christine A.; Dorrian, Gareth D.
Affiliation: AA(Univ. of California, San Diego (USA)), AB(Univ.
of California, San Diego (USA)), AC(Univ. of Wales,
Aberystwyth (United Kingdom)), AD(Univ. of Wales,
Aberystwyth (United Kingdom)), AE(Univ. of
California, San Diego (USA)), AF(EISCAT Scientific
Association (Sweden)), AG(MERLIN/VLBI National
Facility (United Kingdom)), AH(MERLIN/VLBI National
Facility (United Kingdom)), AI(Univ. of Wales,
Aberystwyth (United Kingdom))
Publication: Solar Physics and Space Weather Instrumentation II.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 6689, pp.
668911-668911-10 (2007).
Publication Date: 09/2007
Origin: SPIE
Abstract Copyright: (c) 2007: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.735443
Bibliographic Code: 2007SPIE.6689E..31B
Abstract
The technique of interplanetary scintillation (IPS) can be used to probe
interplanetary space between the Sun and Earth most-commonly in terms of
speed and also by using the scintillation-level (g-level) as a proxy for
density. We combine the large spatial-scale 3D tomographic techniques
previously only applied to IPS data from the Solar Terrestrial
Environment Laboratory (STELab) array, Nagoya University in Japan, and
the previously operational Cambridge IPS system in England, with the
finer-scale capabilities of the longer baselines between the systems of
the Multi-Element Radio-Linked Interferometer Network (MERLIN) in the
UK, and the European Incoherent SCATter (EISCAT) radar and the EISCAT
Svalbard Radar (ESR) in northern Scandinavia. Using the UCSD 3D
reconstruction technique, we present results of detailed measurements of
speed in the solar wind and also those of solar wind flow-directions,
constrained by the large-scale density tomography through the use of a
kinematic model, as well as applying this tomographic technique for the
first time to the MERLIN, EISCAT, and ESR IPS solar wind speed
observations in terms of velocity.
Title: SMEI observations in the STEREO era
Authors: Jackson, Bernard V.; Buffington, Andrew;
Hick, P. Paul; Bisi, Mario M.; Jensen, Elizabeth A.
Affiliation: AA(Univ. of California, San Diego (USA)), AB(Univ.
of California, San Diego (USA)), AC(Univ. of
California, San Diego (USA)), AD(Univ. of
California, San Diego (USA)), AE(Univ. of
California, San Diego (USA))
Publication: Solar Physics and Space Weather Instrumentation II.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 6689, pp.
66890G-66890G-14 (2007).
Publication Date: 09/2007
Origin: SPIE
Abstract Copyright: (c) 2007: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.734870
Bibliographic Code: 2007SPIE.6689E..12J
Abstract
White-light Thomson scattering observations from the Solar Mass Ejection
Imager (SMEI) have recorded the inner heliospheric response to many
CMEs. Some of these are also observed from the LASCO instrumentation
and, most recently, the STEREO spacecraft. Here, we detail several CME
events in SMEI observations that have also been observed by the LASCO
instrumentation and STEREO spacecrafts. We show how SMEI is able to
measure CME events from their first observations as close as 20°
from the solar disk until they fade away in the SMEI 180° field of
view. We employ a 3D reconstruction technique that provides perspective
views as observed from Earth, from outward-flowing solar wind. This is
accomplished by iteratively fitting the parameters of a kinematic solar
wind density model to the SMEI white-light observations and, where
possible, including interplanetary scintillation (IPS) velocity data.
This 3D modeling technique enables separating the true heliospheric
response in SMEI from background noise, and reconstructing the 3D
heliospheric structure as a function of time. These reconstructions
allow both separation of CME structure from other nearby heliospheric
features and a determination of CME mass. Comparisons with LASCO and
STEREO images for individual CMEs or portions of them allow a detailed
view of changes to the CME shape and mass as they propagate outward.
Title: A procedure for fitting point sources in SMEI
white-light full-sky maps
Authors: Hick, P.; Buffington, A.; Jackson, B. V.
Affiliation: AA(Univ. of California, San Diego (USA)), AB(Univ.
of California, San Diego (USA)), AC(Univ. of
California, San Diego (USA))
Publication: Solar Physics and Space Weather Instrumentation II.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 6689, pp.
66890C-66890C-8 (2007).
Publication Date: 09/2007
Origin: SPIE
Abstract Copyright: (c) 2007: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.734808
Bibliographic Code: 2007SPIE.6689E...9H
Abstract
The Solar Mass Ejection Imager (SMEI) instrument consists of three CCD
cameras with individual fields of view of 60° × 3° degrees
that combined sweep a 160° arc of sky. SMEI covers the entire sky in
one spacecraft orbit of 102 minutes. Individual 4-s exposures from each
orbit are assembled into full-sky maps. The primary objective in the
SMEI data reduction is to isolate the Thomson-scattering signal across
the sky from free electrons in the solar wind. One of the steps needed
to achieve the required photometric precision is the individual fitting
and removal of stars brighter than 6th magnitude from the full-sky maps.
The point-spread function of the SMEI optics has several unusual
properties. It has a full width of about one degree, is asymmetric, and
varies in width depending on where in the field of view the image is
formed. Moreover, the orientation of the PSF on the sidereal sky rotates
over 360 degree over the course of a year. We describe the procedure
used to fit and subtract individual stars from the SMEI full-sky maps. A
by-product of this procedure are time series at the orbital time
resolution for stars brighter than 6th magnitude. These results are used
by Buffington et al. (2007) to calibrate the SMEI instrument against the
LASCO C3 coronagraph.
Title: Analysis of the comparative responses of SMEI and
LASCO
Authors: Buffington, Andrew; Morrill, Jeff S.; Hick, P. Paul;
Howard, Russell A.; Jackson, Bernard V.;
Webb, David F.
Affiliation: AA(Univ. of California, San Diego (USA)), AB(Naval
Research Lab. (USA)), AC(Univ. of California, San
Diego (USA)), AD(Naval Research Lab. (USA)),
AE(Univ. of California, San Diego (USA)), AF(Boston
College (USA))
Publication: Solar Physics and Space Weather Instrumentation II.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 6689, pp.
66890B-66890B-6 (2007).
Publication Date: 09/2007
Origin: SPIE
Abstract Copyright: (c) 2007: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.734658
Bibliographic Code: 2007SPIE.6689E...8B
Abstract
Surface-brightness responses of the SOHO-LASCO C3 coronagraph and of the
Solar Mass Ejection Imager (SMEI) are compared, using measurements of a
selection of bright stars that have been observed in both instruments.
Seventeen stars are selected that are brighter than 4.5 magnitudes, are
not known variables, and do not have a neighboring bright star.
Comparing observations of these determines a scaling relationship
between surface-brightness measurements from one instrument to those
from the other. We discuss units of surface brightness for the two
instruments, and estimate a residual uncertainty for the present scaling
relationship.
Title: How Does Large Flaring Activity from the Same Active
Region Produce Oppositely Directed Magnetic Clouds?
Authors: Harra, Louise K.; Crooker, Nancy U.;
Mandrini, Cristina H.; van Driel-Gesztelyi, Lidia;
Dasso, Sergio; Wang, Jingxiu; Elliott, Heather;
Attrill, Gemma; Jackson, Bernard V.; Bisi, Mario M.
Affiliation: AA(Mullard Space Science Laboratory, University
College London), AB(Center for Space Physics, Boston
University), AC(Instituto de Astronomía y Física del
Espacio, CONICET-UBA), AD(Mullard Space Science
Laboratory, University College London; ,
Observatoire de Paris, LESIA, FRE 2461 (CNRS)),
AE(Instituto de Astronomía y Física del Espacio,
CONICET-UBA; Departamento de Física, Facultad de
Ciencias Exactas y Naturales, Universidad de Buenos
Aires), AF(National Astronomical Observatory,
Chinese Academy of Sciences), AG(Southwest Research
Institute), AH(Mullard Space Science Laboratory,
University College London), AI(Center for
Astrophysics and Space Sciences, University of
California), AJ(Center for Astrophysics and Space
Sciences, University of California)
Publication: Solar Physics, Volume 244, Issue 1-2, pp. 95-114
Publication Date: 08/2007
Origin: SPRINGER
DOI: 10.1007/s11207-007-9002-x
Bibliographic Code: 2007SoPh..244...95H
Abstract
We describe the interplanetary coronal mass ejections (ICMEs) that
occurred as a result of a series of solar flares and eruptions from 4 to
8 November 2004. Two ICMEs/magnetic clouds occurring from these events
had opposite magnetic orientations. This was despite the fact that the
major flares related to these events occurred within the same active
region that maintained the same magnetic configuration. The solar events
include a wide array of activities: flares, trans-equatorial coronal
loop disappearance and reformation, trans-equatorial filament eruption,
and coronal hole interaction. The first major ICME/magnetic cloud was
predominantly related to the active region 10696 eruption. The second
major ICME/magnetic cloud was found to be consistent with the magnetic
orientation of an erupting trans-equatorial filament or else a rotation
of 160° of a flux rope in the active region. We discuss these
possibilities and emphasize the importance of understanding the magnetic
evolution of the solar source region before we can begin to predict
geoeffective events with any accuracy.
Title: The Laplace transform on time scales revisited
Authors: Davis, John M.; Gravagne, Ian A.; Jackson, Billy J.;
Marks, Robert J., II; Ramos, Alice A.
Publication: Journal of Mathematical Analysis and Applications,
Vol. 332, No. 2, p. 1291-1307
Publication Date: 08/2007
Origin: AUTHOR
Keywords: Time scale, Laplace transform, Convolution, Dirac
delta
Bibliographic Code: 2007JMAA..332.1291D
Abstract
In this work, we reexamine the time scale Laplace transform as defined
by Bohner and Peterson [M. Bohner, A. Peterson, Dynamic Equations on
Time Scales: An Introduction with Applications, Birkhauser, Boston,
2001; M. Bohner, A. Peterson, Laplace transform and Z-transform:
Unification and extension, Methods Appl. Anal. 9 (1) (2002) 155-162]. In
particular, we give conditions on the class of functions which have a
transform, develop an inversion formula for the transform, and further,
we provide a convolution for the transform. The notion of convolution
leads to considering its algebraic structure--in particular the
existence of an identity element--motivating the development of the
Dirac delta functional on time scales. Applications and examples of
these concepts are given.
Title: Matter Wave Solitons at Finite Temperatures
Authors: Jackson, B.; Barenghi, C. F.; Proukakis, N. P.
Affiliation: AA(School of Mathematics and Statistics, University
of Newcastle upon Tyne), AB(School of Mathematics
and Statistics, University of Newcastle upon Tyne),
AC(School of Mathematics and Statistics, University
of Newcastle upon Tyne)
Publication: Journal of Low Temperature Physics, Volume 148,
Issue 3-4, pp. 387-391
Publication Date: 08/2007
Origin: SPRINGER
Keywords: 03.75.Lm, 05.45.Yv, 67.80.Gb
Abstract Copyright: (c) 2007: Springer Science+Business Media, LLC
DOI: 10.1007/s10909-007-9410-1
Bibliographic Code: 2007JLTP..148..387J
Abstract
We consider the dynamics of a dark soliton in an elongated harmonically
trapped Bose-Einstein condensate. A central question concerns the
behavior at finite temperatures, where dissipation arises due to the
presence of a thermal cloud. We study this problem using coupled
Gross-Pitaevskii and N-body simulations, which include the mean field
coupling between the condensate and thermal cloud. We find that the
soliton decays relatively quickly even at very low temperatures, with
the decay rate increasing with rising temperature.
Title: Tidal Evolution of Extrasolar Planets
Authors: Jackson, Brian; Greenberg, R.; Barnes, R.
Affiliation: AA(University of Arizona, Lunar and Planetary Lab),
AB(University of Arizona, Lunar and Planetary Lab),
AC(University of Arizona, Lunar and Planetary Lab)
Publication: American Astronomical Society, DDA meeting \#38,
\#15.02
Publication Date: 07/2007
Origin: AAS
Bibliographic Code: 2007DDA....38.1502J
Abstract
Eccentricities e of extrasolar planets with semimajor axes a > 0.1 AU
are large, averaging 0.24 and broadly distributed up to near 1. For
smaller a, eccentricities are much smaller (most < 0.2), which is
widely attributed to damping by tides after the planets formed and the
gaseous disk dissipated. Previous estimates of the damping rates
considered the tide raised on the planet by the star, but ignored the
tide raised on the star. Also, specific values were assumed for the
planet's poorly constrained tidal dissipation parameter Q. Perhaps most
important, the strongly coupled evolution between a and e was ignored.
We have now integrated the full coupled tidal evolution equations for e
and a over the estimated age of each planet, and confirm that the
distribution of initial e values of close-in planets can match that of
the general population. Eccentricity distributions are best matched for
stellar and planetary Q values of 1e5 and 1e6, respectively. The
accompanying coupled tidal evolution of the a values (mutually dependent
on the evolution of e) was also significant: At the start of tidal
migration, all planets had a > 0.06 AU, significantly larger than
current values. It appears that gas disk migration did not bring planets
closer than 0.06 AU, and that the current smaller values of a were only
reached gradually due to tides over the lifetimes of the planets. Models
of the early physical evolution of "hot Jupiters'' should take into
account that those planets were significantly farther from the stars
when the gas disk dissipated than they are now.
Title: Dark-soliton dynamics in Bose-Einstein condensates
at finite temperature
Authors: Jackson, B.; Proukakis, N. P.; Barenghi, C. F.
Affiliation: AA(School of Mathematics and Statistics, University
of Newcastle upon Tyne, Newcastle upon Tyne, NE1
7RU, United Kingdom), AB(School of Mathematics and
Statistics, University of Newcastle upon Tyne,
Newcastle upon Tyne, NE1 7RU, United Kingdom),
AC(School of Mathematics and Statistics, University
of Newcastle upon Tyne, Newcastle upon Tyne, NE1
7RU, United Kingdom)
Publication: Physical Review A, vol. 75, Issue 5, id. 051601
Publication Date: 05/2007
Origin: APS
Abstract Copyright: (c) 2007: The American Physical Society
DOI: 10.1103/PhysRevA.75.051601
Bibliographic Code: 2007PhRvA..75e1601J
Abstract
The dynamics of a dark soliton in an elongated Bose-Einstein condensate
is studied at finite temperatures. In addition to accurately reproducing
all stages of the decay of the soliton observed in the experiment of
Burger [Phys. Rev. Lett. 83, 5198 (1999)], our numerical simulations
reveal the existence of an experimentally accessible parameter regime
for which phase-imprinted dark solitons can execute at least one full
axial oscillation prior to their decay. The dependence of the decay time
scale on temperature and initial soliton depth is analyzed and the role
of interatomic collisions quantified.
Title: The source and propagation of the interplanetary
disturbance associated with the full-halo coronal
mass ejection on 28 October 2003
Authors: Tokumaru, Munetoshi; Kojima, Masayoshi;
Fujiki, Ken'ichi; Yamashita, Masahiro;
Jackson, Bernard V.
Affiliation: AA(Solar-Terrestrial Environment Laboratory, Nagoya
University, Nagoya, Japan); AB(Solar-Terrestrial
Environment Laboratory, Nagoya University, Nagoya,
Japan); AC(Solar-Terrestrial Environment Laboratory,
Nagoya University, Nagoya, Japan);
AD(Solar-Terrestrial Environment Laboratory, Nagoya
University, Nagoya, Japan); AE(Center for
Astrophysics and Space Science, University of
California at San Diego, La Jolla, California, USA)
Publication: Journal of Geophysical Research, Volume 112, Issue
A5, CiteID A05106
Publication Date: 05/2007
Origin: AGU
AGU Keywords: Interplanetary Physics: Coronal mass ejections
(7513), Interplanetary Physics: Ejecta, driver
gases, and magnetic clouds, Interplanetary Physics:
Solar wind plasma, Interplanetary Physics:
Interplanetary shocks
DOI: 10.1029/2006JA012043
Bibliographic Code: 2007JGRA..11205106T
Abstract
Observations of interplanetary scintillations made with the 327-MHz
four-station system of the Solar-Terrestrial Environment Laboratory of
Nagoya University were analyzed to study the three-dimensional
properties of a transient solar wind stream associated with the 28
October 2003 full-halo coronal mass ejection (CME). A loop-shaped
high-density regionregion propagating at a significantly slower speed
than the CME-driven shock was identified. This feature appeared
approximately the same as the structure seen in white-light observations
made simultaneously. The orientation of the loop structure was found in
general agreement with the inclination of the magnetic flux rope
observed at 1 AU. Therefore we propose that the origin of this loop
structure included the high-density plasma ejected from the corona in
association with the 28 October 2003 CME. By comparing this loop
structure with solar wind speed data, we find that the loop structure
had a solar source aligned with a slow-speed solar wind regionregion.
Title: CME 3D Reconstructions Using Solar Mass Ejection
Imager and Interplanetary Scintillation Data
Authors: Jackson, Bernard V.; Bisi, M. M.; Hick, P. P.;
Buffington, A.
Affiliation: AA(UC, San Diego), AB(UC, San Diego), AC(UC, San
Diego), AD(UC, San Diego)
Publication: American Astronomical Society Meeting 210, \#29.23;
Bulletin of the American Astronomical Society, Vol.
38, p.141
Publication Date: 05/2007
Origin: AAS
Bibliographic Code: 2007AAS...210.2923J
Abstract
Solar Mass Ejection Imager (SMEI) and interplanetary scintillation (IPS)
observations provide a view of the solar wind at all solar elongations;
from 180 degrees anti-solar to as close to the Sun as coronagraph fields
of view. They can be used to study the evolution of the solar wind and
solar transients out into interplanetary space. In addition, the inner
heliospheric response to corotating solar structures and coronal mass
ejections (CMEs) can be measured, both in scintillation level and in
velocity when using IPS, and through Thomson Scattering when using SMEI.
We use a 3D reconstruction technique that obtains perspective views from
solar corotating plasma and outward-flowing solar wind as observed from
Earth, by iteratively fitting a kinematic solar wind model to both SMEI
and IPS observations. This 3D modeling technique permits reconstructions
of the density and velocity structures of CMEs and other interplanetary
transients. These reconstructions have a temporal cadence and
heliographic latitudinal and longitudinal resolution predicated by the
amount of data used for time-dependent reconstructions, and can use data
from a variety of IPS instruments distributed around the Earth. We
highlight the 3D analyses of these different data sets using a series of
CME events observed beginning on the Sun 4-7 November 2004. We also
apply this technique to determine solar wind pressure (``ram''
pressure) at Mars. Results are compared with ram pressure observations
derived from Mars Global Surveyor magnetometer data for the years 1999
through 2004, and include a reconstruction of a ``back-side''
event as seen by SOHO/LASCO.
Title: Analysis of Solar Wind Events Using Interplanetary
Scintillation Remote Sensing 3D Reconstructions and
Their Comparison at Mars
Authors: Jackson, B. V.; Boyer, J. A.; Hick, P. P.;
Buffington, A.; Bisi, M. M.; Crider, D. H.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California), AB(Center for
Astrophysics and Space Sciences, University of
California), AC(Center for Astrophysics and Space
Sciences, University of California), AD(Center for
Astrophysics and Space Sciences, University of
California), AE(Center for Astrophysics and Space
Sciences, University of California), AF(Catholic
University of America)
Publication: Solar Physics, Volume 241, Issue 2, pp.385-396
Publication Date: 04/2007
Origin: SPRINGER
DOI: 10.1007/s11207-007-0276-9
Bibliographic Code: 2007SoPh..241..385J
Abstract
Interplanetary Scintillation (IPS) allows observation of the inner
heliospheric response to corotating solar structures and coronal mass
ejections (CMEs) in scintillation level and velocity. With colleagues at
STELab, Nagoya University, Japan, we have developed near-real-time
access of STELab IPS data for use in space-weather forecasting. We use a
3D reconstruction technique that produces perspective views from solar
corotating plasma and outward-flowing solar wind as observed from Earth
by iteratively fitting a kinematic solar wind model to IPS observations.
This 3D modeling technique permits reconstruction of the density and
velocity structure of CMEs and other interplanetary transients at a
relatively coarse resolution: a solar rotational cadence and 10°
latitudinal and longitudinal resolution for the corotational model and a
one-day cadence and 20° latitudinal and longitudinal heliographic
resolution for the time-dependent model. This technique is used to
determine solar-wind pressure (``ram'' pressure) at Mars.
Results are compared with ram-pressure observations derived from Mars
Global Surveyor magnetometer data (Crider et al. 2003, J. Geophys. Res.
108(A12), 1461) for the years 1999 through 2004. We identified 47
independent in situ pressure-pulse events above 3.5 nPa in the Mars
Global Surveyor data in this time period where sufficient IPS data were
available. We detail the large pressure pulse observed at Mars in
association with a CME that erupted from the Sun on 27 May 2003, which
was a halo CME as viewed from Earth. We also detail the response of a
series of West-limb CME events and compare their response observed at
Mars about 160° west of the Sun Earth line by the Mars Global
Surveyor with the response derived from the IPS 3D reconstructions.
Title: Methane Dissociation on Ni(111): The Role of Lattice
Reconstruction
Authors: Nave, Sven; Jackson, Bret
Affiliation: AA(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA),
AB(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003, USA)
Publication: Physical Review Letters, vol. 98, Issue 17, id.
173003
Publication Date: 04/2007
Origin: APS
Abstract Copyright: (c) 2007: The American Physical Society
DOI: 10.1103/PhysRevLett.98.173003
Bibliographic Code: 2007PhRvL..98q3003N
Abstract
The effects of lattice motion and reconstruction on the dissociation of
methane on Ni(111) are explored, using both electronic structure theory
and quantum dynamical calculations. We show that during the reaction,
the Ni lattice reconstructs, effectively lowering the barrier to
reaction, in contrast with earlier models of this process.
Title: Vortices in Bose-Einstein Condensates: Theory
Authors: Parker, N. G.; Jackson, B.; Martin, A. M.;
Adams, C. S.
Publication: eprint arXiv:0704.0146
Publication Date: 04/2007
Origin: ARXIV
Keywords: Condensed Matter - Other
Comment: 17 pages, 2 figures. Book chapter to appear in
"Emergent Nonlinear Phenomena in Bose-Einstein
condensates: Theory and Experiment"
(Springer-Verlag).
Bibliographic Code: 2007arXiv0704.0146P
Abstract
Vortices are pervasive in nature, representing the breakdown of laminar
fluid flow and hence playing a key role in turbulence. The fluid
rotation associated with a vortex can be parameterized by the
circulation $\Gamma=\oint {\rm d}{\bf r}\cdot{\bf v}({\bf r})$ about the
vortex, where ${\bf v}({\bf r})$ is the fluid velocity field. While
classical vortices can take any value of circulation, superfluids are
irrotational, and any rotation or angular momentum is constrained to
occur through vortices with quantized circulation. Quantized vortices
also play a key role in the dissipation of transport in superfluids. In
BECs quantized vortices have been observed in several forms, including
single vortices, vortex lattices, and vortex pairs and rings. The recent
observation of quantized vortices in a fermionic gas was taken as a
clear signature of the underlying condensation and superfluidity of
fermion pairs. In addition to BECs, quantized vortices also occur in
superfluid Helium, nonlinear optics, and type-II superconductors.
Title: Integrated optoelectronics in an optical fiber
Authors: Badding, J. V.; Sazio, P. J.; Gopalan, V.;
Amezcua Correa, Adrian; Scheidemantel, T. J.;
Finlayson, C. E.; Baril, N. F.; Jackson, B. R.;
Won, D.
Affiliation: AA(Pennsylvania State Univ. (USA)), AB(Univ. of
Southampton (United Kingdom)), AC(Pennsylvania State
Univ. (USA)), AD(Univ. of Southampton (United
Kingdom)), AE(Pennsylvania State Univ. (USA)),
AF(Univ. of Southampton (United Kingdom)),
AG(Pennsylvania State Univ. (USA)), AH(Pennsylvania
State Univ. (USA)), AI(Pennsylvania State Univ.
(USA))
Publication: Integrated Optics: Devices, Materials, and
Technologies XI. Edited by Sidorin, Yakov;
Waechter, Christoph A.. Proceedings of the SPIE,
Volume 6475, pp. 64750N (2007).
Publication Date: 03/2007
Origin: SPIE
Abstract Copyright: (c) 2007: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.700725
Bibliographic Code: 2007SPIE.6475E..20B
Abstract
Integration of semiconductor and metal structures into optical fibers to
enable fusion of semiconductor optoelectronic function with glass
optical fibers is discussed. A chemical vapor deposition (CVD)-like
process, adapted for high pressure flow within microstructured optical
fibers allows for flexible fabrication of such structures. Integration
of semiconductor optoelectronic devices such as lasers, detectors, and
modulators into fibers may now become possible.
Title: Maxmaxflow and counting subgraphs
Authors: Jackson, Bill; Sokal, Alan D.
Publication: eprint arXiv:math/0703585
Publication Date: 03/2007
Origin: ARXIV
Keywords: Mathematics - Combinatorics, Mathematical Physics,
05C99 (Primary), 05C15, 05C30, 05C35, 05C40, 82B20,
90B10 (Secondary)
Comment: Latex2e, 47 pages (includes 2 figures)
Bibliographic Code: 2007math......3585J
Abstract
We introduce a new graph invariant \Lambda(G) that we call maxmaxflow,
and put it in the context of some other well-known graph invariants,
notably maximum degree and its relatives. We prove the equivalence of
two "dual" definitions of maxmaxflow: one in terms of flows, the other
in terms of cocycle bases. We then show how to bound the total number
(or more generally, total weight) of various classes of subgraphs of G
in terms of either maximum degree or maxmaxflow. We conclude with some
conjectures concerning the relevance of maxmaxflow to the roots of
chromatic polynomials.
Title: Solar Mass Ejection Imager (SMEI) observations of
coronal mass ejections (CMEs) in the heliosphere
Authors: Webb, D. F.; Mizuno, D. R.; Buffington, A.;
Cooke, M. P.; Eyles, C. J.; Fry, C. D.;
Gentile, L. C.; Hick, P. P.; Holladay, P. E.;
Howard, T. A.; Hewitt, J. G.; Jackson, B. V.;
Johnston, J. C.; Kuchar, T. A.; Mozer, J. B.;
Price, S.; Radick, R. R.; Simnett, G. M.;
Tappin, S. J.
Affiliation: AA(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA);
AB(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA);
AC(Center for Astrophysics and Space Sciences
(CASS), University of California, San Diego, La
Jolla, California, USA); AD(School of Physics and
Astronomy, University of Birmingham, Birmingham,
UK); AE(School of Physics and Astronomy, University
of Birmingham, Birmingham, UK); AF(Exploration
Physics International, Incorporated, Huntsville,
Alabama, USA); AG(Institute for Scientific Research,
Boston College, Chestnut Hill, Massachusetts, USA);
AH(Center for Astrophysics and Space Sciences
(CASS), University of California, San Diego, La
Jolla, California, USA); AI(Air Force Research
Laboratory, Space Vehicles Directorate, Hanscom Air
Force Base, Massachusetts, USA); AJ(Physics
Department, Montana State University, Bozeman,
Montana, USA); AK(Air Force Research Laboratory,
Space Vehicles Directorate, Hanscom Air Force Base,
Massachusetts, USA); AL(Center for Astrophysics and
Space Sciences (CASS), University of California, San
Diego, La Jolla, California, USA); AM(Air Force
Research Laboratory, Space Vehicles Directorate,
Hanscom Air Force Base, Massachusetts, USA);
AN(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA); AO(Air
Force Research Laboratory, Space Vehicles
Directorate, Hanscom Air Force Base, Massachusetts,
USA); AP(Air Force Research Laboratory, Space
Vehicles Directorate, Hanscom Air Force Base,
Massachusetts, USA); AQ(Air Force Research
Laboratory, Space Vehicles Directorate, Sunspot, New
Mexico, USA); AR(School of Physics and Astronomy,
University of Birmingham, Birmingham, UK); AS(School
of Physics and Astronomy, University of Birmingham,
Birmingham, UK)
Publication: Journal of Geophysical Research, Volume 111, Issue
A12, CiteID A12101
Publication Date: 12/2006
Origin: AGU
AGU Keywords: Interplanetary Physics: Coronal mass ejections
(7513), Interplanetary Physics: Ejecta, driver
gases, and magnetic clouds, Space Weather: Magnetic
storms (2788), Solar Physics, Astrophysics, and
Astronomy: Prominence eruptions, Interplanetary
Physics: Solar wind sources
DOI: 10.1029/2006JA011655
Bibliographic Code: 2006JGRA..11112101W
Abstract
The Solar Mass Ejection Imager (SMEI) on the Coriolis spacecraft has
been obtaining white light images of nearly the full sky every 102
minutes for three years. We present statistical results of analysis of
the SMEI observations of coronal mass ejections (CMEs) traveling through
the inner heliosphere; 139 CMEs were observed during the first 1.5 years
of operations. At least 30 of these CMEs were observed by SMEI to
propagate out to 1 AU and beyond and were associated with major
geomagnetic storms at Earth. Most of these were observed as frontside
halo events by the SOHO LASCO coronagraphs.
Title: Reduced density matrix quantum approach for particle
trapping and sticking on corrugated moving surfaces
Authors: Medina, Zuleika; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003
Publication: Journal of Chemical Physics, Volume 125, Issue 22,
pp. 224703-224703-11 (2006).
Publication Date: 12/2006
Origin: AIP
Keywords: copper, helium neutral atoms, surface phonons,
atom-surface impact, adsorption
Abstract Copyright: (c) 2006: American Institute of Physics
DOI: 10.1063/1.2402164
Bibliographic Code: 2006JChPh.125v4703M
Abstract
A short time propagation algorithm for the reduced density matrix is
derived to model the interaction of a quantum particle with a moving
corrugated surface. The algorithm includes dissipative terms, which can
be derived directly from the full Hamiltonian. The scattering of He from
a corrugated Cu surface is examined as a function of incident energy and
angle and the temperature of the substrate, with a focus on the nature
of trapping. It is found that corrugation can make a significant
contribution to trapping, even on a metal surface. Energy exchange with
the phonons is shown to significantly modify the nature of diffraction
mediated selective adsorption.
Title: 3-D Magnetic Field Geometry of the October 28, 2003
ICME: Comparison with SMEI White-Light Observations
Authors: Jensen, E. A.; Mulligan, T.; Jackson, B. V.;
Tokumaru, M.
Affiliation: AA(Institute of geophysics and Planetary Physics,
Universtiy of California Los Angeles, 405 Hilgard
Ave, Los Angeles, CA 90024 United States;
Laboratory, The Aerospace Corporation, P.O. Box
92957, M2-260, Los Angeles, CA 90009 United States;
Engineering Research Facility, University of
California San Diego, CASS / UCSD 0424 9500 Gilman
Drive, La Jolla, CA 92093 United States;
Environment Laboratory, Nagoya University, Honohara
3-13, Toyokawa, Aichi, 442-8507 Japan;
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#SH33A-0397
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 6023 Comets: dust tails and trails (6210), 7513
Coronal mass ejections (2101), 7539 Stellar
astronomy, 7924 Forecasting (2722), 7954 Magnetic
storms (2788)
Bibliographic Code: 2006AGUFMSH33A0397J
Abstract
Multiple reconstructions of the October 28-29, 2003 CME/ICME using
white-light observations, ground-based cosmic-ray and in situ magnetic
field flux rope modeling show two possible flux-rope configurations that
pass Earth on opposite sides of the central symmetry axis of the
disturbance. An analysis of flux rope model geometries initiated over a
wide range in parameter space to test the uniqueness of the single
spacecraft inversion reveals the fit is degenerate over a range of
impact parameters such that two solutions are obtained. In one case (fit
A) the disturbance passes Earth to the west of the rope center with the
rope axis at a low inclination of 20 deg to the ecliptic, similar to the
ground-based flux rope analysis by Kuwabara et al.~(2004). In the second
case (fit B) the disturbance passes Earth to the east of the flux rope
axis, with the rope axis more highly inclined at 42 deg from the
ecliptic, consistent with the SMEI white-light analysis of Jackson et
al.~(2006). The current densities in both solutions indicate a nearly
force-free structure. Multipoint studies of ICMEs show the radius of
curvature in the plane of the rope is between that of a dipole field
line connected to the Sun and that of a circular field line connected to
the Sun. Assuming a dipole field geometry for the large- scale axial
field curvature of the rope results in a 3-D reconstruction for case B
that is consistent with the loop structure and observed speed in the
white-light LASCO images and SMEI density reconstruction, but not for
case A. Multipoint measurements of large-scale solar wind transients is
one of the key objectives of the Stereo mission, allowing more accurate
3-D reconstructions of in situ data for comparison with white-light
observations. Until they become available, the large-scale axial field
orientation and loop geometry of these rope reconstructions provides
another tool to constrain magnetic flux rope fits of ICMEs using single
spacecraft measurements.
Title: The 20 January 2005 CME Solar Mass Ejection Imager
(SMEI) Analyses
Authors: Jackson, B. V.; Hick, P. P.; Buffington, A.
Affiliation: AA(CASS/UCSD, CASS UCSD 0424, LaJolla, CA 92093-0424
CASS UCSD 0424, LaJolla, CA 92093-0424 United States
LaJolla, CA 92093-0424 United States;
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#SH33A-0396
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 2111 Ejecta, driver gases, and magnetic clouds, 2139
Interplanetary shocks, 2164 Solar wind plasma, 7513
Coronal mass ejections (2101), 7514 Energetic
particles (2114)
Bibliographic Code: 2006AGUFMSH33A0396J
Abstract
Solar Mass Ejection Imager (SMEI) brightness measurements are analyzed
to determine 3D volumetric densities for several CMEs including that of
the 20 January 2005 CME. Here we present analyses of these 3D
heliospheric volumetric solar wind density analyses. We use this system
to measure the distribution of structure and provide a 3D mass of the
ejecta associated with the large CMEs viewed in SMEI observations. In
the case of the 20 January 2005 CME, the primary mass moves to the
northwest of the Sun following the event observed earlier in LASCO
coronagraph observations. There are two other very large coronal
responses to the coronal energy input beginning around 6:30 UT near the
time of CME onset. One of these is the large and extremely prompt Solar
Energetic Particle (SEP) proton event observed at Earth beginning about
6:50 UT. Another response is an outward-propagating fast shock that
arrives at Earth 34 hours following the event onset. A response that
may be attributed to this shock is observed slightly more than 5 days
following this at the Ulysses spacecraft situated 5.3 AU from the Sun,
17 degrees south of the ecliptic, and 27 degrees from the Sun-Earth line
to the west. SMEI observes the white-light response of this shock at
Earth in the interplanetary medium around the spacecraft, and limits the
shock extent in 3D.
Title: The Evolution of Comets in the Heliosphere as
Observed by SMEI
Authors: Kuchar, T.; Buffington, A.; Howard, T.; Arge, C. N.;
Webb, D.; Jackson, B. V.; Hick, P. P.
Affiliation: AA(Boston College, Institute for Scientific Research
140 Commonwealth Ave., Chestnut Hill, MA 02467
AB(University of California, San Diego, Center for
Astrophysics & Space Sciences 9500 Gilman Drive, La
Jolla, CA 92093 United States;
University, Physics Dept., Bozeman, MT 59717 United
AD(Air Force Research Lab, VSBXS 29 Randolph Road,
Hanscom AFB, MA 01731 United States;
Institute for Scientific Research 140 Commonwealth
Ave., Chestnut Hill, MA 02467 United States;
California, San Diego, Center for Astrophysics &
Space Sciences 9500 Gilman Drive, La Jolla, CA 92093
of California, San Diego, Center for Astrophysics &
Space Sciences 9500 Gilman Drive, La Jolla, CA 92093
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#SH32A-08
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 6023 Comets:
dust tails and trails (6210), 6025 Interactions with
solar wind plasma and fields, 6210 Comets (6023),
7999 General or miscellaneous
Bibliographic Code: 2006AGUFMSH32A..08K
Abstract
Comet observations have been used as in situ probes of the heliospheric
environment since they were used to confirm the existence of the solar
wind. Changes in a comet tail's appearance are attributed to changes in
the solar wind flow. Large scale tail disruptions are usually
associated with boundary crossings of the current sheet or, more rarely,
impacts from coronal mass ejections. The Solar Mass Ejection Imager
(SMEI) observed three bright comets during April-May 2004: Bradfield
(C/2004 F4), LINEAR (C/2002 T7), and NEAT (C/2001 Q4). We had
previously reported several comet tail disconnection events (DEs) for
both NEAT and LINEAR. Investigation of the entire period further
reveals that these two comets showed continual changes in their plasma
tails. These changes are characterized by a "smokestack-like" billowing
effect punctuated by the disconnections. Bradfield however was
remarkably quiescent during this entire period. We present these
extended comet observations and offer an analysis and cause of the
similarities and disparities of these data.
Title: An Empirical Description of Zodiacal Light as
Measured by SMEI
Authors: Buffington, A.; Jackson, B. V.; Hick, P.;
Price, S. D.
Affiliation: AA(University of California San Diego, Center for
Astrophysics and Space Sciences, 9500 Gilman Drive,
La Jolla, CA 92093 United States;
San Diego, Center for Astrophysics and Space
Sciences, 9500 Gilman Drive, La Jolla, CA 92093
of California San Diego, Center for Astrophysics and
Space Sciences, 9500 Gilman Drive, La Jolla, CA
Force Research Laboratory, Space Vehicles
Directorate, Hanscom AFB, 29 Randolph Road, Boston,
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#SH32A-06
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 2129 Interplanetary dust
Bibliographic Code: 2006AGUFMSH32A..06B
Abstract
The SMEI visible-light cameras provide a photometric skymap for each
102-minute orbit with the objective to observe transient Coronal Mass
Ejections (CMEs). Zodiacal light is a significant contributor to these
maps and must be removed in the data-analysis in order to detect and
characterize the much fainter CMEs. We have analyzed over three years of
the SMEI calibration data that were taken at the highest spatial
resolution to derive the yearly averaged global distribution of zodiacal
light between solar elongations of 20 and 180 degrees. Residuals on the
individual sky maps from this global average provide information on the
detailed geometry of the clouds. We present preliminary results of the
analysis, including a characterization of the Gegenschein, possible dust
bands, and annual variations.
Title: CME Brightness at Large Elongations: Application to
LASCO and SMEI Observations
Authors: Vourlidas, A.; Webb, D. F.; Morrill, J. S.;
Jackson, B. V.
Affiliation: AA(Naval Research Laboratory, 4555 Overlook Ave, SW,
Washington, DC 20375 United States;
St. Clements Hall, Rm. 420 140 Commonwealth Ave,
Chestnut Hill,, MA 02467 United States;
Laboratory, 4555 Overlook Ave, SW, Washington, DC
AD(CASS, UCSD, La Jolla, CA 92093 United States;
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#SH32A-03
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections (2101), 7594 Instruments
and techniques
Bibliographic Code: 2006AGUFMSH32A..03V
Abstract
The traditional analysis of the CME brightness relied on the assumption
that all lines of sight through the CME were parallel due to the large
distance between the observer and the event. However, this assumption is
not correct when CME observations at large distances from the Sun are
concerned. In a recent paper (Vourlidas & Howard 2006) we have
outlined the proper geometry and presented a few theoretical predictions
about the brightness evolution of CME launched at various angles
relative to the Sun-observer line. In this talk, we use LASCO and SMEI
observations of the same events to test our predictions and see how we
can use our theoretical framework to interpret the observed CME
structures.
Title: Goals and Progress of the LWS Focused Science Topic
on the CME--ICME Connection
Authors: Mikic, Z.; Deforest, C.; Devore, R.; Georgoulis, M.;
Jackson, B.; Nitta, N.; Pizzo, V.; Odstrcil, D.
Affiliation: AA(SAIC, 10260 Campus Point Drive, San Diego, CA
1050 Walnut Street Suite 400, Boulder, CO 80302
AC(NRL, Code 6440 4555 Overlook Avenue SW,
Washington, DC 20375 United States;
Hopkins Rd., Laurel, MD 20723 United States;
for Astrophysics and Space Sciences 0424 9500 Gilman
Drive, La Jolla, CA 92093 United States;
3251 Hanover Street, Palo Alto, CA 94304 United
Broadway, Boulder, CO 80305 United States;
Boulder, CO 80305 United States;
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#SH21B-05
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 2134 Interplanetary magnetic fields, 7509 Corona,
7513 Coronal mass ejections (2101), 7524 Magnetic
fields
Bibliographic Code: 2006AGUFMSH21B..05M
Abstract
Our team addresses the NASA Living With a Star (LWS) Focused Science
Topic "to determine the solar origins of the plasma and magnetic flux
observed in an interplanetary Coronal Mass Ejection (ICME)." In short,
this team is examining the CME--ICME connection. Our team was formed as
a result of awards from the LWS Targeted Research &Technology
competition in the fall of 2004. Our team is investigating the detailed
relationship between the plasma and magnetic fields in active regions,
the source regions of CMEs, and subsequent in situ measurements in
interplanetary magnetic clouds. We plan to study this connection through
detailed numerical simulations of CME initiation and propagation,
theoretical investigations, and studies of the properties of active
regions, CMEs, and magnetic clouds. We will discuss the goals of our
team, how it fits into NASA's missions, and our progress so far.
Research supported by NASA's Living With a Star Program.
Title: Calibration and Uncertainty Analysis of Water and
Solute Transport Models Within Vegetated Soils Using
a Detailed Dataset
Authors: Jackson, B.; Wheater, H.; Butler, A.
Affiliation: AA(Imperial College London, Department of Civil and
Environmental Engineering Imperial College London
South Kensington, London, SW72AZ United Kingdom;
London, Department of Civil and Environmental
Engineering Imperial College London South
Kensington, London, SW72AZ United Kingdom;
London, Department of Civil and Environmental
Engineering Imperial College London South
Kensington, London, SW72AZ United Kingdom;
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#H41I-03
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 1846 Model calibration (3333), 1852 Plant uptake,
1866 Soil moisture, 1873 Uncertainty assessment
(3275), 1875 Vadose zone
Abstract Copyright: (c) 2006: American Geophysical Union
Bibliographic Code: 2006AGUFM.H41I..03J
Abstract
Appropriate models predicting the fate and transport of water and
dissolved chemicals in vegetated soils are required for a wide range of
applications. Substantial uncertainty is present due to measurement
errors, parametric uncertainty, and structural issues related to model
conceptualisation. Due to the costs and intrusiveness of subsurface
measurements there are limited datasets available to interrogate models
against. Furthermore, the models are typically computationally
intensive, making it difficult to fully explore parametric and other
uncertainty spaces. Hence there are two pressing needs which must be met
to improve the utility of models: more data and constraints are needed
to quantify the interactions between different uncertainties and their
overall impact on the reliability and robustness of model outputs, and
efficient methodologies to explore sensitivities and uncertainties are
also called for. This paper presents a combined analysis of a
particularly detailed dataset and models of water and solute movement,
using both simple random search and Markov chain Monte Carlo methods.
Data was collected from an outdoor vegetated lysimeter facility over a
duration of close to a year, with soil matric potential, moisture
content and temperature at 10 cm depth intervals, along with rainfall
and other meteorological variables, logged in four instrumented
lysimeters at a time interval of 0.01 days. Three radionuclides (Na-22,
Cl-36 and Cs-137) were supplied through the base of the lysimeters using
an automated water table control system. Periodic soil cores and plant
cuttings provided information on their migration and uptake. The
integrity of the experimental data is examined, with uncertainty
associated with outputs discussed and quantified. To interpret the data,
a Richards' equation model coupled to a dynamic plant water model is
linked to an advection-dispersion model with additional process
representations of sorption, radioactive decay and root uptake.
Structural uncertainty, parameterisation issues, and perturbation
effects due to erroneous inputs are discussed. It is shown that although
parameters are difficult to constrain in a univariate sense,
consideration of model structure allows constraints on parametric
interactions and hence a significant reduction of the parametric space
that must be sampled. The efficiency of Markov Chain Monte Carlo
techniques is demonstrated. However, despite the unusually comprehensive
experimental dataset, major issues of uncertainty remain, of which data
issues are a dominant component.
Title: The Impact of Upland Land Management on Flooding:
Results from a Multi-Scale Experimental and
Modelling Programme
Authors: McIntyre, N.; Frogbrook, Z.; Francis, O.;
Jackson, B.; Jenkins, B.; Marshall, M.; Solloway, I.;
Wheater, H.
Affiliation: AA(Imperial College London, Department of Civil and
Environmental Engineering Imperial College London
South Kensington, London, SW72AZ United Kingdom;
Building Deiniol Road, Bangor, LL57 2UP;
Department of Civil and Environmental Engineering
Imperial College London South Kensington, London,
SW72AZ United Kingdom;
College London, Department of Civil and
Environmental Engineering Imperial College London
South Kensington, London, SW72AZ United Kingdom;
Bangor Orton Building Deiniol Road, Bangor, LL57
Department of Civil and Environmental Engineering
Imperial College London South Kensington, London,
AG(Imperial College London, Department of Civil and
Environmental Engineering Imperial College London
South Kensington, London, SW72AZ United Kingdom;
College London, Department of Civil and
Environmental Engineering Imperial College London
South Kensington, London, SW72AZ United Kingdom;
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#H13B-1401
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 1821 Floods, 1834 Human impacts, 1839 Hydrologic
scaling, 1850 Overland flow
Abstract Copyright: (c) 2006: American Geophysical Union
Bibliographic Code: 2006AGUFM.H13B1401M
Abstract
In response to a growing awareness of flood risk and questions as to the
impact of land use management on this, an extensive dataset is currently
being collected within the Pontbren catchment in Wales. This catchment,
predominately covered with heavy clay soil, has a long history of land
drainage and intensifying, but otherwise unchanging, land use. Focus on
Pontbren was driven by local farmers noting increased water runoff, and
the mitigating effect on this of tree-planted areas. A preliminary study
within the catchment indicated that strategically placed, small scale
planting of trees could improve the infiltration capacity of grazed
permanent pasture. Following this, an intensive experimental programme
was initiated to further examine how changes in land use might impact at
different spatial scales. Stream flow, soil water potentials, overland
flow and drain flow, precipitation, and other climatic variables are
continuously monitored, and soil hydraulic properties and runoff
processes are being investigated under different land use treatments
including woodland buffer strips and no grazing management. An
associated modelling programme is using these data to inform development
and calibration of models examining the effects of land use change over
differing spatial scales and levels of process representation. A
multi-dimensional Richards' equation soil water model with macropore and
overland flow representations is used to examine dominant processes at
the hillslope scale. These processes, with associated parameters
conditioned on experimental data, are then used to examine appropriate
model representations and parameterisation at larger scales. Preliminary
results from both the experimental dataset and the physically based
modelling are presented, with a focus on the potential of localised
strategic changes to land-use for reduction of flood risk at hillslope
and catchment scales. Specifically, the implications of introducing a
small tree strip to a grassed, clay hillslope is investigated through
both analysis of current data and interrogation of a physically based
model partially conditioned on measurements from a hillslope site.
Results are preliminary, but indicative of the sensitivity of the system
to the vegetative effects. Changes to soil infiltration rate, hillslope
storage of water and interception properties are shown to be
significant, and the strips appear to be capable of substantially
perturbing the hillslope hydrological response. Issues of scaling and
the need for further supporting data are discussed.
Title: Arctic Ocean Snowmelt Onset Dates Derived from
Passive Microwave for 1979- 2005.
Authors: Anderson, M. R.; Molthan, A. L.; Jackson, B. A.
Affiliation: AA(Department of Geosciences, 214 Bessey Hall,
Lincoln, NE 68588-0340 United States;
Bessey Hall, Lincoln, NE 68588-0340 United States;
Geosciences, 214 Bessey Hall, Lincoln, NE 68588-0340
Publication: American Geophysical Union, Fall Meeting 2006,
abstract \#C21D-03
Publication Date: 12/2006
Origin: AGU
AGU Keywords: 0740 Snowmelt, 0750 Sea ice (4540), 1616 Climate
variability (1635, 3305, 3309, 4215, 4513), 1640
Remote sensing (1855)
Abstract Copyright: (c) 2006: American Geophysical Union
Bibliographic Code: 2006AGUFM.C21D..03A
Abstract
The Arctic Ocean is an integral part of the global climate system and an
area that is observing record breaking seasonal fluctuations. This study
investigates the spring snowmelt onset conditions in the Arctic sea ice
cover from 1979 to 2005. Snowmelt onset over Arctic sea ice is defined
as the point in time when liquid water appears in the snowpack.
Physically, the timing of snowmelt onset is important because surface
energy absorption increases rapidly at snowmelt onset, owing to changes
in surface albedo values. Monitoring the timing of snowmelt onset over
Arctic sea ice is facilitated by using passive microwave data, because
surface microwave emission changes rapidly when liquid water appears in
the snowpack, and data acquisitions are relatively unaffected by cloud
cover or solar illumination. The Advanced Horizontal Range Algorithm
(AHRA) exploits the changes in passive microwave brightness temperatures
between 18GHz (19GHz on SSM/I) and 37GHz brightness temperatures to
derive snow melt onset dates over Arctic sea ice from 1979-2005.
Comparison between AHRA-derived melt onset dates and temperatures from
International Arctic Buoy Program/Polar Exchange at the Sea Surface
(IABP/POLES) and NCEP/NCAR Reanalysis-2 illustrates melt onset typically
occurs when air temperatures near 0oC. The objective of this paper is
to examine the melt onset dates for the Arctic region and discuss the
trends in the dates over the period studied. In addition, ice reduction
dates are calculated and compared to the melt onset dates to further
understand the melt characteristics during the spring. The ice reduction
date is when the ice concentration drops below 80%. Both the melt onset
and ice reduction dates are derived from passive microwave remote
sensing. There is a notable period of time, delta t, between the melt
onset and ice reduction. Analysis of delta t for the Arctic over the
microwave record provides explanations for changes in sea ice cover over
time. For instance, an anomalously short delta t could be an outcome of
an atmospheric pattern that brings unseasonably warm temperatures to the
region, reducing the ice concentrations. However, the same delta t could
be a result of thinner ice being melted in the same time period with
less warm air advection. In general, the results continue to show a
trend to earlier melt onset dates. However the melt onset dates for the
more recent years do not show extremely earlier dates, even though the
ice cover at the end of the melt season continues to show reduced
perennial ice cover in October. The ice reduction dates also show
earlier dates, which would indicate a shorter melt season and possible
thinner ice cover which is not melting earlier, but is being removed
quicker in the spring. Understanding the surface energy budget could be
used to determine why patterns in ice concentration and extent occur
during certain years, but not for others.
Title: Hysteresis effects in rotating Bose-Einstein
condensates
Authors: Jackson, B.; Barenghi, C. F.
Affiliation: AA(Dipartimento di Fisica, Università di Trento and
CNR-INFM R&D Center on Bose-Einstein Condensation,
I-38050 Povo, Italy; School of Mathematics and
Statistics, University of Newcastle upon Tyne,
NE1 7RU, United Kingdom), AB(School of Mathematics
and Statistics, University of Newcastle upon Tyne,
NE1 7RU, United Kingdom)
Publication: Physical Review A, vol. 74, Issue 4, id. 043618
Publication Date: 10/2006
Origin: APS
Abstract Copyright: (c) 2006: The American Physical Society
DOI: 10.1103/PhysRevA.74.043618
Bibliographic Code: 2006PhRvA..74d3618J
Abstract
We study the formation of vortices in a dilute Bose-Einstein condensate
confined in a rotating anisotropic trap. We find that the number of
vortices and angular momentum attained by the condensate depend upon the
rotation history of the trap and on the number of vortices present in
the condensate initially. A simplified model based on hydrodynamic
equations is developed, and used to explain this effect in terms of a
shift in the resonance frequency of the quadrupole mode of the
condensate in the presence of a vortex lattice. Differences between the
spin-up and spin-down response of the condensate are found,
demonstrating hysteresis phenomena in this system.
Title: A simple model of variable residence time flow and
nutrient transport in the chalk
Authors: Jackson, Bethanna M.; Wheater, Howard S.;
Mathias, Simon A.; McIntyre, Neil; Butler, Adrian P.
Affiliation: Department of Civil and Environmental Engineering,
Imperial College London, London SW7 2BU, United
Kingdom. Corresponding author. Tel.: +44 1491 692
328; fax: +44 1491 692 345.
Publication: Journal of Hydrology, Volume 330, Issue 1-2, p.
221-234.
Publication Date: 10/2006
Origin: ELSEVIER
Abstract Copyright: Elsevier B.V.
DOI: 10.1016/j.jhydrol.2006.04.045
Bibliographic Code: 2006JHyd..330..221J
Abstract
A basic problem of modelling flow and transport in Chalk catchments
arises from the existence of a deep unsaturated zone, with complex
interactions between flow in fractures and water held in the fine pores
of the rock matrix. The response of the water table to major
infiltration episodes is rapid (of the order of days). However, chemical
signals are strongly damped, suggesting that this water is of varying
age, with a corresponding mixed history of nutrient loading. Clearly
this effect should be represented in any model of nutrients in Chalk
systems. The applicability of simplified physically-based model
formulations to represent the dual response in an integrated way has
been investigated by a variety of researchers, but it has been shown
that these approximations break down in application to the Chalk.
Mathias et al. [Mathias, S., Butler, A.P., Jackson, B.M., Wheater, H.S.,
this issue. Characterising flow in the Chalk unsaturated zone. In:
Wheater, H.S., Peach, D., Neal, C, editors, Hydrology on LOCAR in the
Pang/Lambourn, special issue of J. Hydrol,
doi:10.1016/j.jhydrol.2006.04.010] present a dual permeability model
that explains the observed response, but such complex formulations are
not readily incorporated in catchment-scale nutrient models. This paper
reviews previous approaches to modelling the Chalk and then presents a
pragmatic approach, with transport of solute and water through the
unsaturated zone treated separately, and combined at the water table.
Varying residence times are included through considering the distance
between the water table and the soil surface, and the history of
nutrient application at the surface. If an average rate of downwards
migration of the nutrients is assumed, it is possible to derive a travel
time distribution of nitrate transport to the water table using a DTM
(digital terrain model) map of elevation and information on groundwater
levels. This distribution can then be implemented through difference
equations. The rationale behind the model and the resulting algorithm is
described, and the algorithm then applied to a hypothetical case study
of nutrient loading located in the Lambourn, a groundwater-dominated
Chalk catchment in Southern England. Simulated groundwater
concentrations are very similar in magnitude and variability to observed
Chalk groundwater series, suggesting that this simple conceptual model
may well be able to capture the dominant responses of nutrient transport
through the Chalk.
Title: Transient simulations of flow and transport in the
Chalk unsaturated zone
Authors: Mathias, S. A.; Butler, A. P.; Jackson, B. M.;
Wheater, H. S.
Affiliation: Department of Civil and Environmental Engineering,
Imperial College London, South Kensington Campus,
London SW7 2AZ, UK. Corresponding author. Tel.: +44
20 75946120.
Publication: Journal of Hydrology, Volume 330, Issue 1-2, p.
10-28.
Publication Date: 10/2006
Origin: ELSEVIER
Abstract Copyright: Elsevier B.V.
DOI: 10.1016/j.jhydrol.2006.04.010
Bibliographic Code: 2006JHyd..330...10M
Abstract
Chalk is a fractured porous medium composed of matrix blocks bounded by
interconnected fractures. Furthermore, there are a number of commonly
observed, and apparently contradictory, phenomena. These include: a fast
water table response, slow solute migration and very little solute
dispersion. To the authors' knowledge, no unified
physically-based, numerical model has been able to reconcile all of
these points. In this paper, these issues were addressed through the
development of a transient dual-permeability model of flow and
transport. The behaviour of the model was explored through a
hypothetical scenario. The one-dimensional model featured a fixed water
table at 10 m depth. A recharge time-series, derived using the Penman
Grindley model in conjunction with daily precipitation and monthly
potential evaporation data from the Kennet valley, Berkshire, was
applied at the top of the model. A conservative solute (that could be
tritium, chloride or nitrate) was applied to the recharge for 1 year.
Subsequent years involved the input of clean water. The simulations
suggested that although transient effects have been previously
neglected, overlying soil and gravelly chalk layers are likely to cause
significant attenuating effects on flow such that most flow occurs
through the matrix. Fracture flow was found to be episodic and
infrequent and represented between 17% and 30% of the annual recharge.
Title: Improved helium exchange gas cryostat and sample
tube designs for automated gas sampling and
cryopumping
Authors: Buerki, P. R.; Jackson, Brian C.; Schilling, Tim;
Rufer, Terry; Severinghaus, Jeffrey P.
Affiliation: AA(Geosciences Research Division, Scripps
Institution of Oceanography, Department 0244,
University of California, San Diego, 9500 Gilman
Drive, La Jolla, California, 92093-0244, USA);
AB(Advanced Research Systems, Inc., 7476 Industrial
Park Way, Macungie, Pennsylvania, 18062, USA);
AC(Advanced Research Systems, Inc., 7476 Industrial
Park Way, Macungie, Pennsylvania, 18062, USA);
AD(Advanced Research Systems, Inc., 7476 Industrial
Park Way, Macungie, Pennsylvania, 18062, USA);
AE(Geosciences Research Division, Scripps
Institution of Oceanography, Department 0244,
University of California, San Diego, 9500 Gilman
Drive, La Jolla, California, 92093-0244, USA)
Publication: Geochemistry Geophysics Geosystems, Volume 7, Issue
10, CiteID Q10010
Publication Date: 10/2006
Origin: AGU
AGU Keywords: Cryosphere: Ice cores (4932), Geochemistry: Stable
isotope geochemistry (0454, 4870), Geochemistry:
Instruments and techniques
Abstract Copyright: (c) 2006: American Geophysical Union
DOI: 10.1029/2006GC001341
Bibliographic Code: 2006GGG.....710010B
Abstract
In order to eliminate the use of liquid helium for the extraction of
atmospheric gases from polar ice cores, two units of a redesigned top
load helium exchange gas cryostat were built and tested. The cryostats
feature the shortest and largest diameter sample wells built to date, a
base temperature below 7 Kelvin, and a sample well without baffles. The
cryostats allowed shortening the length and thus increasing the gas
pressure inside our sample tubes by 58% and increasing the amount of
sample ending up in the mass spectrometer by 4.4%. The cryostats can
either be used as mobile stand-alone units for manual gas processing
lines or integrated into a fully automated vacuum extraction and gas
analysis line. For the latter application the cryostat was equipped with
a custom-designed automated changeover system.
Title: BiSON update
Authors: Allison, J.; Barnes, I.; Chaplin, W.J.;
Elsworth, Y.P.; Hale, S.J.; Jackson, B.;
Miller, B.A.; Verner, G.A.; New, R.
Publication: Proceedings of SOHO 18/GONG 2006/HELAS I, Beyond the
spherical Sun (ESA SP-624). 7-11 August 2006,
Sheffield, UK. Editor: Karen Fletcher. Scientific
Editor: Michael Thompson, Published on CDROM, p.99.1
Publication Date: 10/2006
Origin: ADS
Bibliographic Code: 2006ESASP.624E..99A
Abstract
Not Available
Title: International Colloquium "Scattering and
Scintillation in Radio Astronomy" was held on June
19-23, 2006 in Pushchino, Moscow region, Russia
Authors: Shishov, V. I.; Coles, W. A.; Rickett, B. J.;
Bird, M. K.; Efimov, A. I.; Samoznaev, L. N.;
Rudash, V. K.; Chashei, I. V.; Plettemeier, D.;
Spangler, S. R.; Tokarev, Yu.; Belov, Yu.; Boiko, G.;
Komrakov, G.; Chau, J.; Harmon, J.; Sulzer, M.;
Kojima, M.; Tokumaru, M.; Fujiki, K.; Janardhan, P.;
Jackson, B. V.; Hick, P. P.; Buffington, A.;
Olyak, M. R.; Fallows, R. A.; Nechaeva, M. B.;
Gavrilenko, V. G.; Gorshenkov, Yu. N.; Alimov, V. A.;
Molotov, I. E.; Pushkarev, A. B.; Shanks, R.;
Tuccari, G.; Lotova, N. A.; Vladimirski, K. V.;
Obridko, V. N.; Gubenko, V. N.; Andreev, V. E.;
Stinebring, D.; Gwinn, C.; Lovell, J. E. J.;
Jauncey, D. L.; Senkbeil, C.; Shabala, S.;
Bignall, H. E.; Macquart, J. -P.; Rickett, B. J.;
Kedziora-Chudczer, L.; Smirnova, T. V.;
Rickett, B. J.; Malofeev, V. M.; Malov, O. I.;
Tyulbashev, S. A.; Jessner, A.; Sieber, W.;
Wielebinski, R.
Publication: eprint arXiv:astro-ph/0609517
Publication Date: 09/2006
Origin: ARXIV
Keywords: Astrophysics
Comment: 20 pages, astrophysical conference
Bibliographic Code: 2006astro.ph..9517S
Abstract
Topics of the Colloquium: a) Interplanetary scintillation b)
Interstellar scintillation c) Modeling and physical origin of the
interplanetary and the interstellar plasma turbulence d) Scintillation
as a tool for investigation of radio sources e) Seeing through
interplanetary and interstellar turbulent media Ppt-presentations are
available on the Web-site: http://www.prao.ru/conf/Colloquium/main.html
Title: Performance of the flight model HIFI band 3 and 4
mixer units
Authors: de Lange, G.; Jackson, B. D.; Jochemsen, M.;
Laauwen, W. M.; de Jong, L.; Kroug, M.; Zijlstra, T.;
Klapwijk, T. M.
Affiliation: AA(SRON Netherlands Institute for Space Research
(Netherlands)), AB(SRON Netherlands Institute for
Space Research (Netherlands)), AC(SRON Netherlands
Institute for Space Research (Netherlands)), AD(SRON
Netherlands Institute for Space Research
(Netherlands)), AE(SRON Netherlands Institute for
Space Research (Netherlands)), AF(Delft Univ. of
Technology (Netherlands)), AG(Delft Univ. of
Technology (Netherlands)), AH(Delft Univ. of
Technology (Netherlands))
Publication: Millimeter and Submillimeter Detectors and
Instrumentation for Astronomy III. Edited by
Zmuidzinas, Jonas; Holland, Wayne S.; Withington,
Stafford; Duncan, William D.. Proceedings of the
SPIE, Volume 6275, pp. 627517 (2006).
Publication Date: 07/2006
Origin: SPIE
DOI: 10.1117/12.673870
Bibliographic Code: 2006SPIE.6275E..39D
Abstract
We describe the performance of the Band 3 and Band 4 Flight Model mixer
units for Herschel/HIFI Instrument. These units are part of the Focal
Plane Unit of HIFI. The band 3 and 4 mixer units cover the 800-960 GHz
and 960-1120 GHz frequency range and have a 4-8 GHz IF frequency band.
The sensitivities of the mixers within the HIFI setting are excellent
and are the best reported to date. The DSB receiver noise performance in
the HIFI FPU environment ranges from 150 K at 800 GHz to 350 K at 1120
GHz. This sensitivity and the absence of atmospheric attenuation will
reduce the necessary observation time for astronomical observations in
this frequency range by at least two orders of magnitude compared to
ground based facilities.
Title: ESPRIT: a space interferometer concept for the
far-infrared
Authors: Wild, W.; de Graauw, Th.; Helmich, F.;
Cernicharo, J.; Gunst, A.; Bos, A.;
den Herder, J.-W.; Jackson, B.;
van Langevelde, H.-J.; Maat, P.; Martin-Pintado, J.;
Noordam, J.; Quirrenbach, A.; Roelfsema, P.;
Venema, L.; Wesselius, P.; Yagoubov, P.
Affiliation: AA(SRON Netherlands Institute for Space Research
(Netherlands) and Univ. of Groningen (Netherlands)),
AB(SRON Netherlands Institute for Space Research
(Netherlands) and Leiden Observatory (Netherlands)),
AC(SRON Netherlands Institute for Space Research
(Netherlands)), AD(CSIC (Spain)), AE(ASTRON
(Netherlands)), AF(ASTRON (Netherlands)), AG(SRON
Netherlands Institute for Space Research
(Netherlands)), AH(SRON Netherlands Institute for
Space Research (Netherlands)), AI(ASTRON
(Netherlands)), AJ(ASTRON (Netherlands)), AK(CSIC
(Spain)), AL(ASTRON (Netherlands)), AM(Leiden
Observatory (Netherlands)), AN(SRON Netherlands
Institute for Space Research (Netherlands) and Univ.
of Groningen (Netherlands)), AO(ASTRON
(Netherlands)), AP(SRON Netherlands Institute for
Space Research (Netherlands) and Univ. of Groningen
(Netherlands)), AQ(SRON Netherlands Institute for
Space Research (Netherlands))
Publication: Space Telescopes and Instrumentation I: Optical,
Infrared, and Millimeter. Edited by Mather, John
C.; MacEwen, Howard A.; de Graauw, Mattheus W. M..
Proceedings of the SPIE, Volume 6265, pp. 62651Z
(2006).
Publication Date: 07/2006
Origin: SPIE
DOI: 10.1117/12.672012
Bibliographic Code: 2006SPIE.6265E..59W
Abstract
In the far-infrared (FIR) / THz regime the angular (and often spectral)
resolution of observing facilities is still very restricted despite the
fact that this frequency range has become of prime importance for modern
astrophysics. ALMA (Atacama Large Millimeter Array) with its superb
sensitivity and angular resolution will only cover frequencies up to
about 1 THz, while the HIFI instrument for ESA'a Herschel Space
Observatory will provide limited angular resolution (10 to 30 arcsec) up
to 2 THz. Observations of regions with star and planet formation require
extremely high angular resolution as well as frequency resolution in the
full THz regime. In order to open these regions for high-resolution
astrophysics we propose a heterodyne space interferometer mission,
ESPRIT (Exploratory Submm Space Radio-Interferometric Telescope), for
the Terahertz regime inaccessible from ground and outside the operating
range of the James Webb Space Telescope (JWST).
Title: The Optical Harness: a light-weight EMI-immune
replacement for legacy electrical wiring harnesses
Authors: Stark, Jason B.; Jackson, B. Scott;
Trethewey, William
Affiliation: AA(Defense Photonics Group (USA)), AB(Defense
Photonics Group (USA)), AC(Defense Photonics Group
(USA))
Publication: Enabling Photonics Technologies for Defense,
Security, and Aerospace Applications II. Edited by
Hayduk, Michael J.; Pirich, Andrew R.; Donkor, Eric
J.; Delfyett, Peter J., Jr.. Proceedings of the
SPIE, Volume 6243, pp. 624309 (2006).
Publication Date: 06/2006
Origin: SPIE
Abstract Copyright: (c) 2006: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.666583
Bibliographic Code: 2006SPIE.6243E...7S
Abstract
Electrical wiring harnesses have been used to interconnect control and
communication equipment in mobile platforms for over a century. Although
they have served this function successfully, they have three problems
that are inherent in their design: they are mechanically heavy and
stiff, and they are prone to electrical faults, including arcing and
Electro-Magnetic Interference (EMI), and they are difficult to maintain
when faults occur. These properties are all aspects of the metallic
conductors used to build the harnesses. The Optical HarnessTM
is a photonic replacement for the legacy electrical wiring harness. The
Optical HarnessTM uses light-weight optical fiber to replace
signal wires in an electrical harness. The original electrical
connections to the equipment remain, making the Optical
HarnessTM a direct replacement for the legacy wiring harness.
In the backshell of each connector, the electrical signals are converted
to optical, and transported on optical fiber, by a deterministic,
redundant and fault-tolerant optical network. The Optical
HarnessTM: * Provides weight savings of 40-50% and
unsurpassed flexibility, relative to legacy signal wiring harnesses; *
Carries its signals on optical fiber that is free from arcing, EMI, RFI
and susceptibility to HPM weapons; * Is self-monitoring during
operation, providing non-intrusive predictive and diagnostic
capabilities.
Title: From the Cover: Eugenol and isoeugenol,
characteristic aromatic constituents of spices, are
biosynthesized via reduction of a coniferyl alcohol
ester
Authors: Koeduka, Takao; Fridman, Eyal; Gang, David R.;
Vassão, Daniel G.; Jackson, Brenda L.;
Kish, Christine M.; Orlova, Irina;
Spassova, Snejina M.; Lewis, Norman G.;
Noel, Joseph P.; Baiga, Thomas J.; Dudareva, Natalia;
Pichersky, Eran
Publication: Proceedings of the National Academy of Science, vol.
103, Issue 26, p.10128-10133
Publication Date: 06/2006
Category: BIOLOGICAL SCIENCES / PLANT BIOLOGY
Origin: PNAS
DOI: 10.1073/pnas.0603732103
Bibliographic Code: 2006PNAS..10310128K
Abstract
Phenylpropenes such as chavicol, t-anol, eugenol, and isoeugenol are
produced by plants as defense compounds against animals and
microorganisms and as floral attractants of pollinators. Moreover,
humans have used phenylpropenes since antiquity for food preservation
and flavoring and as medicinal agents. Previous research suggested that
the phenylpropenes are synthesized in plants from substituted
phenylpropenols, although the identity of the enzymes and the nature of
the reaction mechanism involved in this transformation have remained
obscure. We show here that glandular trichomes of sweet basil (Ocimum
basilicum), which synthesize and accumulate phenylpropenes, possess an
enzyme that can use coniferyl acetate and NADPH to form eugenol. Petunia
(Petunia hybrida cv. Mitchell) flowers, which emit large amounts of
isoeugenol, possess an enzyme homologous to the basil eugenol-forming
enzyme that also uses coniferyl acetate and NADPH as substrates but
catalyzes the formation of isoeugenol. The basil and petunia
phenylpropene-forming enzymes belong to a structural family of
NADPH-dependent reductases that also includes pinoresinol-lariciresinol
reductase, isoflavone reductase, and phenylcoumaran benzylic ether
reductase. floral scent | phenylpropanoids | phenylpropenes | plant
volatiles | secondary compounds
Title: Generation of the primary hair follicle pattern
Authors: Mou, Chunyan; Jackson, Ben; Schneider, Pascal;
Overbeek, Paul A.; Headon, Denis J.
Publication: Proceedings of the National Academy of Science, vol.
103, Issue 24, p.9075-9080
Publication Date: 06/2006
Category: BIOLOGICAL SCIENCES / DEVELOPMENTAL BIOLOGY
Origin: PNAS
DOI: 10.1073/pnas.0600825103
Bibliographic Code: 2006PNAS..103.9075M
Abstract
Hair follicles are spaced apart from one another at regular intervals
through the skin. Although follicles are predominantly epidermal
structures, classical tissue recombination experiments indicated that
the underlying dermis defines their location during development.
Although many molecules involved in hair follicle formation have been
identified, the molecular interactions that determine the emergent
property of pattern formation have remained elusive. We have used
embryonic skin cultures to dissect signaling responses and patterning
outcomes as the skin spatially organizes itself. We find that
ectodysplasin receptor (Edar)-bone morphogenetic protein (BMP) signaling
and transcriptional interactions are central to generation of the
primary hair follicle pattern, with restriction of responsiveness,
rather than localization of an inducing ligand, being the key driver in
this process. The crux of this patterning mechanism is rapid
Edar-positive feedback in the epidermis coupled with induction of dermal
BMP4/7. The BMPs in turn repress epidermal Edar and hence follicle fate.
Edar activation also induces connective tissue growth factor, an
inhibitor of BMP signaling, allowing BMP action only at a distance from
their site of synthesis. Consistent with this model, transgenic
hyperactivation of Edar signaling leads to widespread overproduction of
hair follicles. This Edar-BMP activation-inhibition mechanism appears to
operate alongside a labile prepattern, suggesting that Edar-mediated
stabilization of -catenin active foci is a key event in determining
definitive follicle locations. pattern formation | reaction-diffusion |
skin development
Title: Design and development of a 600-720 GI-1z receiver
for ALMA Band 9
Authors: Baryshev, A. M.; Hesper, R.; Mena, F. P.;
Jackson, B. D.; Adema, J.; Schaeffer, H.;
Barkhof, J.; Wild, W.; Candotti, M.; Lodewijk, C.;
Loudkov, D.; Zijlstra, T.; Noroozian, 0.;
Klapwijk, T. M.
Publication: Seventeenth International Symposium on Space
Terahertz Technology, held May 10-12, 2006 at
Observatoire de Paris, LERMA. Paris, France., p.89
Publication Date: 05/2006
Origin: NRAO
Bibliographic Code: 2006stt..conf...89B
Abstract
Not Available
Title: The Band 3 and 4 Flight Model mixer units for HIFI
Authors: de Lange, G.; Jackson, B. D.; Eggens, M.;
Golstein, H.; Laauwen, W. M.; de Jong, L.;
Kikken, S.; F'ieters, C.; Smit, H.; van Nguyen, D.;
Zijlstra, T.; Kroug, M.; Klapwijk, T. M.
Publication: Seventeenth International Symposium on Space
Terahertz Technology, held May 10-12, 2006 at
Observatoire de Paris, LERMA. Paris, France., p.88
Publication Date: 05/2006
Origin: NRAO
Bibliographic Code: 2006stt..conf...88D
Abstract
Not Available
Title: An Internet Database of Ultraviolet Continuum Light
Curves for Seyfert Galaxies
Authors: Dunn, Jay P.; Jackson, Brian; Deo, Rajesh P.;
Farrington, Chris; Das, Varendra;
Crenshaw, D. Michael
Affiliation: AA(Department of Physics and Astronomy, Georgia
State University, Atlanta, GA 30303-4106
Laboratory, University of Arizona, Tucson, AZ
85721-0092.), AC(Department of Physics and
Astronomy, Georgia State University, Atlanta, GA
Physics and Astronomy, Georgia State University,
AE(Department of Physics and Astronomy, Georgia
State University, Atlanta, GA 30303-4106
Astronomy, Georgia State University, Atlanta, GA
Publication: The Publications of the Astronomical Society of the
Pacific, Volume 118, Issue 842, pp. 572-579.
Publication Date: 04/2006
Origin: UCP
PASP Keywords: Galaxies: Seyfert, Ultraviolet: Galaxies
DOI: 10.1086/500961
Bibliographic Code: 2006PASP..118..572D
Abstract
Using the Multimission Archive at STScI (MAST), we have extracted
spectra and determined continuum light curves for 175 Seyfert galaxies
that have been observed with the International Ultraviolet Explorer and
the Faint Object Spectrograph on the Hubble Space Telescope. To obtain
the light curves as a function of Julian Date, we used fixed bins in the
object's rest frame and measured small regions (between 30 and 60
Å) of each spectrum's continuum flux in the range 1150 to 3200
Å. We provide access to the UV light curves and other basic
information about the observations in tabular and graphical form via the
Internet at http://www.chara.gsu.edu/PEGA/IUE.
Title: Preliminary three-dimensional analysis of the
heliospheric response to the 28 October 2003 CME
using SMEI white-light observations
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.;
Wang, X.; Webb, D.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AB(Center for Astrophysics and
Space Sciences, University of California, San Diego,
La Jolla, California, USA); AC(Center for
Astrophysics and Space Sciences, University of
California, San Diego, La Jolla, California, USA);
AD(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AE(Institute for Space Research,
Boston College, Chestnut Hill, Massachusetts, USA)
Publication: Journal of Geophysical Research, Volume 111, Issue
A4, CiteID A04S91
Publication Date: 04/2006
Origin: AGU
AGU Keywords: Solar Physics, Astrophysics, and Astronomy: Coronal
mass ejections (2101), Solar Physics, Astrophysics,
and Astronomy: Instruments and techniques,
Interplanetary Physics: Solar wind plasma,
Interplanetary Physics: Instruments and techniques,
Space Plasma Physics: Instruments and techniques
DOI: 10.1029/2004JA010942
Bibliographic Code: 2006JGRA..11104S91J
Abstract
The Solar Mass Ejection Imager (SMEI) has recorded the inner
heliospheric response in white-light Thomson scattering to the 28
October 2003 coronal mass ejection (CME). This preliminary report shows
the evolution of this particular event in SMEI observations, as we track
it from a first measurement at approximately 20° elongation (angular
distance) from the solar disk until it fades in the antisolar hemisphere
in the SMEI 180° field of view. The large angle and spectrometric
coronagraph (LASCO) images show a CME and an underlying bright ejection
of coronal material that is associated with an erupting prominence. Both
of these are seen by SMEI in the interplanetary medium. We employ a
three-dimensional (3-D) reconstruction technique that derives its
perspective views from outward flowing solar wind to reveal the shape
and extent of the CME. This is accomplished by iteratively fitting the
parameters of a kinematic solar wind density model to both SMEI
white-light observations and Solar-Terrestrial Environment Laboratory
(STELab), interplanetary scintillation (IPS) velocity data. This
modeling technique separates the true heliospheric signal in SMEI
observations from background noise and reconstructs the 3-D heliospheric
structure as a function of time. These reconstructions allow separation
of the 28 October CME from other nearby heliospheric structure and a
determination of its mass. The present results are the first utilizing
this type of 3-D reconstruction with the SMEI data. We determine an
excess-over-ambient mass for the southward moving ejecta associated with
the prominence material of 7.1 × 1016 g and a total
mass of 8.9 × 1016 g. Preliminary SMEI white-light
calibration indicates that the total mass of this CME including possible
associated nearby structures may have been as much as ~2.0 ×
1017 g spread over much of the earthward facing hemisphere.
Title: Microstructured Optical Fibers as High-Pressure
Microfluidic Reactors
Authors: Sazio, Pier J. A.; Amezcua-Correa, Adrian;
Finlayson, Chris E.; Hayes, John R.;
Scheidemantel, Thomas J.; Baril, Neil F.;
Jackson, Bryan R.; Won, Dong-Jin; Zhang, Feng;
Margine, Elena R.; Gopalan, Venkatraman;
Crespi, Vincent H.; Badding, John V.
Affiliation: AA(Optoelectronics Research Centre, University of
Southampton, Highfield, Southampton SO17 1BJ, UK.),
AB(Optoelectronics Research Centre, University of
Southampton, Highfield, Southampton SO17 1BJ, UK.),
AC(Optoelectronics Research Centre, University of
Southampton, Highfield, Southampton SO17 1BJ, UK.),
AD(Optoelectronics Research Centre, University of
Southampton, Highfield, Southampton SO17 1BJ, UK.),
AE(Materials Research Institute,; Department of
Physics,), AF(Materials Research Institute,;
Department of Chemistry,), AG(Materials Research
Institute,; Department of Chemistry,), AH(Materials
Research Institute,; Department of Materials Science
and Engineering, Pennsylvania State University,
University Park, PA 16802, USA.), AI(Materials
Research Institute,; Department of Physics,),
AJ(Materials Research Institute,; Department of
Physics,), AK(Materials Research Institute,;
Department of Materials Science and Engineering,
Pennsylvania State University, University Park, PA
16802, USA.), AL(Materials Research Institute,;
Department of Physics,), AM(Materials Research
Institute,; Department of Chemistry,)
Publication: Science, Volume 311, Issue 5767, pp. 1583-1586
(2006).
Publication Date: 03/2006
Category: APP PHYSICS
Origin: SCIENCE
Abstract Copyright: (c) 2006: Science
DOI: 10.1126/science.1124281
Bibliographic Code: 2006Sci...311.1583S
Abstract
Deposition of semiconductors and metals from chemical precursors onto
planar substrates is a well-developed science and technology for
microelectronics. Optical fibers are an established platform for both
communications technology and fundamental research in photonics. Here,
we describe a hybrid technology that integrates key aspects of both
engineering disciplines, demonstrating the fabrication of tubes, solid
nanowires, coaxial heterojunctions, and longitudinally patterned
structures composed of metals, single-crystal semiconductors, and
polycrystalline elemental or compound semiconductors within
microstructured silica optical fibers. Because the optical fibers are
constructed and the functional materials are chemically deposited in
distinct and independent steps, the full design flexibilities of both
platforms can now be exploited simultaneously for fiber-integrated
optoelectronic materials and devices.
Title: Partial dynamic equations on time scales
Authors: Jackson, B.
Publication: Journal of Computational and Applied Mathematics,
vol. 186, p. 391-415
Publication Date: 02/2006
Origin: WEB
Keywords: Time scale, Partial dynamic equation, Laplace
transform, Multivariable calculus, Partial
derivative, Iterated integral
Bibliographic Code: 2006JCoAM.186..391J
Abstract
In this work, we generalize existing ideas of the univariate case of the
time scales calculus to the bivariate case. Formal definitions of
partial derivatives and iterated integrals are offered, and bivariate
partial differential operators are examined. In particular, solutions of
the homogeneous and nonhomogeneous heat and wave operators are found
when initial distributions given are in terms of elementary functions by
means of the generalized Laplace Transform for the time scale setting.
Finally, the so-termed mixed time scale setting is discussed. Examples
are given and solutions are provided in tabular form.
Title: Low-noise 0.8-0.96- and 0.96-1.12-THz
superconductor-insulator-superconductor mixers for
the herschel space observatory
Authors: Jackson, B. D.; de Lange, G.; Zijlstra, T.;
Kroug, M.; Kooi, J. W.; Stern, J. A.;
Klapwijk, T. M.
Publication: IEEE Transactions on Microwave Theory and
Techniques, vol. 54, issue 2, pp. 547-558
Publication Date: 02/2006
Origin: CROSSREF
DOI: 10.1109/TMTT.2005.862717
Bibliographic Code: 2006ITMTT..54..547J
Abstract
Not Available
Title: A Search for Early Optical Emission at Gamma-Ray
Burst Locations by the Solar Mass Ejection Imager
(SMEI)
Authors: Buffington, Andrew; Band, David L.;
Jackson, Bernard V.; Hick, P. Paul; Smith, Aaron C.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California, San Diego, CA 92093-0424
Goddard Space Flight Center, Greenbelt, MD 20771.;
Joint Center for Astrophysics, Physics Department,
University of Maryland Baltimore County, 1000
Hilltop Circle, Baltimore, MD 21250;
Astrophysics and Space Sciences, University of
California, San Diego, CA 92093-0424
Space Sciences, University of California, San Diego,
for Astrophysics and Space Sciences, University of
California, San Diego, CA 92093-0424
Publication: The Astrophysical Journal, Volume 637, Issue 2, pp.
880-888.
Publication Date: 02/2006
Origin: UCP
ApJ Keywords: Gamma Rays: Bursts, Techniques: Photometric
DOI: 10.1086/498407
Bibliographic Code: 2006ApJ...637..880B
Abstract
The Solar Mass Ejection Imager (SMEI) views nearly every point on the
sky once every 102 minutes and can detect point sources as faint as R~10
mag. Therefore, SMEI can detect or provide upper limits for the optical
afterglow from gamma-ray bursts in the tens of minutes after the burst,
when different shocked regions may emit optically. Here we provide upper
limits for 58 bursts between 2003 February and 2005 April.
Title: Vortex signatures in annular Bose-Einstein
condensates
Authors: Cozzini, M.; Jackson, B.; Stringari, S.
Affiliation: AA(Dipartimento di Fisica, Università di Trento and
BEC-INFM, I-38050 Povo, Italy), AB(Dipartimento di
Fisica, Università di Trento and BEC-INFM, I-38050
Povo, Italy; School of Mathematics and Statistics,
Merz Court, University of Newcastle upon Tyne, NE1
7RU, United Kingdom), AC(Dipartimento di Fisica,
Università di Trento and BEC-INFM, I-38050 Povo,
Italy)
Publication: Physical Review A, vol. 73, Issue 1, id. 013603
Publication Date: 01/2006
Origin: APS
Abstract Copyright: (c) 2006: The American Physical Society
DOI: 10.1103/PhysRevA.73.013603
Bibliographic Code: 2006PhRvA..73a3603C
Abstract
We consider a Bose-Einstein condensate confined in a ``Mexican
hat'' or sombrero potential, with a quartic minus quadratic radial
dependence. We find conditions under which the ground state is annular
in shape, with a hole in the center of the condensate. Rotation leads to
the appearance of stable multiply quantized vortices, giving rise to a
superfluid flow around the ring. The collective modes of the system are
explored both numerically and analytically using the Gross-Pitaevskii
and hydrodynamic equations. Potential experimental schemes to detect
vorticity are proposed and evaluated, which include measuring the
splitting of collective-mode frequencies, observing expansion following
release from the trap, and probing the momentum distribution of the
condensate.
Title: Sensitivity analysis of a catchment-scale nitrogen
model
Authors: McIntyre, N.; Jackson, B.; Wade, A. J.;
Butterfield, D.; Wheater, H. S.
Affiliation: AA(Department of Civil and Environmental
Engineering, Imperial College London, South
Kensington, London SW7 2AZ, UK), AB(Department of
Civil and Environmental Engineering, Imperial
College London, South Kensington, London SW7 2AZ,
UK), AC(Aquatic Environments Research Centre,
Department of Geography, The University of Reading,
Reading RG6 6AB, UK), AD(Aquatic Environments
Research Centre, Department of Geography, The
University of Reading, Reading RG6 6AB, UK),
AE(Department of Civil and Environmental
Engineering, Imperial College London, South
Kensington, London SW7 2AZ, UK)
Publication: Journal of Hydrology, Volume 315, Issue 1-4, p.
71-92.
Publication Date: 12/2005
Origin: ELSEVIER
Abstract Copyright: Elsevier B.V.
DOI: 10.1016/j.jhydrol.2005.04.010
Bibliographic Code: 2005JHyd..315...71M
Abstract
There are now considerable expectations that semi-distributed models are
useful tools for supporting catchment water quality management. However,
insufficient attention has been given to evaluating the uncertainties
inherent to this type of model, especially those associated with the
spatial disaggregation of the catchment. The Integrated Nitrogen in
Catchments model (INCA) is subjected to an extensive regionalised
sensitivity analysis in application to the River Kennet, part of the
groundwater-dominated upper Thames catchment, UK The main results are:
(1) model output was generally insensitive to land-phase parameters,
very sensitive to groundwater parameters, including initial conditions,
and significantly sensitive to in-river parameters; (2) INCA was able to
produce good fits simultaneously to the available flow, nitrate and
ammonium in-river data sets; (3) representing parameters as
heterogeneous over the catchment (206 calibrated parameters) rather than
homogeneous (24 calibrated parameters) produced a significant
improvement in fit to nitrate but no significant improvement to flow and
caused a deterioration in ammonium performance; (4) the analysis
indicated that calibrating the flow-related parameters first, then
calibrating the remaining parameters (as opposed to calibrating all
parameters together) was not a sensible strategy in this case; (5) even
the parameters to which the model output was most sensitive suffered
from high uncertainty due to spatial inconsistencies in the estimated
optimum values, parameter equifinality and the sampling error associated
with the calibration method; (6) soil and groundwater nutrient and flow
data are needed to reduce uncertainty in initial conditions, residence
times and nitrogen transformation parameters, and long-term historic
data are needed so that key responses to changes in land-use management
can be assimilated. The results indicate the general difficulty of
reconciling the questions which catchment nutrient models are expected
to answer with typically limited data sets and limited knowledge about
suitable model structures. The results demonstrate the importance of
analysing semi-distributed model uncertainties prior to model
application, and illustrate the value and limitations of using Monte
Carlo-based methods for doing so.
Title: Aperture synthesis in the far-infrared
Authors: Wild, W.; de Graauw, Th.; Helmich, F. P.;
Jackson, B.
Publication: 39TH ESLAB Symposium on Trends in Space Science and
Cosmic Vision 2020, held 19-21 April 2005,
Noordwijk, The Netherlands. Edited by F. Favata, J.
Sanz-Forcada, A. Giménez, and B. Battrick. ESA
SP-588. European Space Agency, 2005., p.327
Publication Date: 12/2005
Origin: ADS
Bibliographic Code: 2005ESASP.588..327W
Abstract
Not Available
Title: VIMS Observations of Titan's South Polar Haze
Authors: Jackson, B. K.; Griffith, C. A.; Cassini VIMS Team
Affiliation: AA(U. Arizona), AB(U. Arizona)
Publication: American Astronomical Society, DPS meeting \#37,
\#45.33; Bulletin of the American Astronomical
Society, Vol. 37, p.1569
Publication Date: 12/2005
Origin: AAS
Bibliographic Code: 2005DPS....37.4533J
Abstract
Titan's stratospheric haze significantly affects the thermal budget of
the atmosphere, thereby providing important dynamical forcing. The
aerosols act as atmospheric coolants by enhancing radiation to space in
the thermal infrared. In addition, they heat the atmosphere by absorbing
solar UV radiation. Atmospheric models which couple the haze to the
dynamics suggest that the aerosols accumulate at the poles during the
winter, creating permanent polar caps, and augment the latitudinal
temperature gradients. In turn, this reinforces meridional circulation
which transports more haze to the pole and results in a positive
feedback between dynamics and cooling.
Ground-based observations in the near-IR (1 to 2 mum) of Titan's south
pole indicate the existence of a polar hood of haze between 30 and 50 km
altitude. Yet, the altitude of these particulates, which coincides with
that of the tropopause at 44 km, raises the question of whether the
particles are methane cloud particles associated with local convection
or haze associated with global circulation. We propose to investigate
further the nature of the polar hood with an analysis of Cassini
observations from the Visual and Infrared Mapping Spectrometer (VIMS),
which provides a higher spatial resolution and greater wavelength
coverage than do the ground-based observations.
Preliminary analysis of the VIMS data corroborates the existence of a
southern polar hood of atmospheric particulates. Through a radiative
transfer analysis, we will determine the optical depth, altitude,
effective particle size and latitudinal extent of the observed
particulate hood. The optical depth will provide a measure of the
thermal forcing due to the particles, while the effective size will
distinguish between submicron-sized haze particles and the larger
methane particles, diagnostic of the hood's origin.
Title: SMEI: A Spaceborne Observatory for Heliospheric
Remote Sensing
Authors: Hick, P.; Jackson, B. V.; Buffington, A.; Yu, Y.
Affiliation: AA(University of California San Diego, Center for
Astrophysics and Space Sciences, 9500 Gilman Drive,
AB(University of California San Diego, Center for
Astrophysics and Space Sciences, 9500 Gilman Drive,
AC(University of California San Diego, Center for
Astrophysics and Space Sciences, 9500 Gilman Drive,
AD(University of California San Diego, Center for
Astrophysics and Space Sciences, 9500 Gilman Drive,
La Jolla, CA 92093-0424 ; )
Publication: American Geophysical Union, Fall Meeting 2005,
abstract \#SH51C-1219
Publication Date: 12/2005
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 2102 Corotating
streams, 7594 Instruments and techniques, 7924
Forecasting (2722)
Bibliographic Code: 2005AGUFMSH51C1219H
Abstract
The Solar Mass Ejection Imager (SMEI) provides measurements of the
Thomson scattering brightness with near-full sky coverage from Earth
orbit. These observations allow three-dimensional reconstruction of the
solar wind density and velocity throughout the inner heliosphere. We
discuss how these observations provide context for in situ solar wind
observations from other "Great Observatory" satellites near Earth (ACE),
other planets (Mars Orbiter) and in deep space (Ulysses).
Title: Global 3-D Solar Wind Analysis of Halo CMEs Using
Interplanetary Scintillation (IPS) Remote Sensing
and its Comparison at Mars
Authors: Boyer, J. A.; Jackson, B. V.; Buffington, A.;
Hick, P. P.; Yu, Y.; Crider, D. H.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AB(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AC(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AD(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
for Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
of America, 106 Driftwood Dr., Gibsonville, NC 27249
Publication: American Geophysical Union, Fall Meeting 2005,
abstract \#SH43A-1145
Publication Date: 12/2005
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 2102 Corotating
streams, 2780 Solar wind interactions with
unmagnetized bodies, 5421 Interactions with
particles and fields, 6929 Ionospheric physics
(1240, 2400)
Bibliographic Code: 2005AGUFMSH43A1145B
Abstract
The Interplanetary Scintillation (IPS) process allows observation of the
inner heliospheric response to CMEs in scintillation level and
velocity. With the help of our colleagues in STELab, Japan, we have
developed near real time access of these data for use in space weather
forecasting. We use a 3D reconstruction technique that obtains
perspective views from outward-flowing solar wind as observed from Earth
by iteratively fitting a kinematic solar wind model using the IPS
observations. This 3D modeling technique permits us to reconstruct the
density and velocity structure of CMEs, and other interplanetary
transient structure at low resolution (with a one day cadence, and at a
20 deg. latitudinal and longitudinal heliographic resolution). Here we
explore the use of this technique to reproduce the solar wind pressure
observed at Mars following the aftermath of halo (Earth-directed) CMEs.
These CMEs include one that erupted from the Sun on May 27, 2003 and
another on October 28, 2003 both of which produced a large response at
Mars. In addition we explore the response at Mars and our
reconstruction of "backside" (as seen from Earth) halo CMEs.
Title: Solar Mass Ejection Imager (SMEI) Solar Wind 3-D
Analysis of the January 20, 2005 CME
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.; Yu, Y.;
Webb, D.
Affiliation: AA(CASS, University of California at San Diego,
LaJolla, CA 92093 United States;
California at San Diego, LaJolla, CA 92093 United
University of California at San Diego, LaJolla, CA
University of California at San Diego, LaJolla, CA
Boston College, Chestnut Hill, MA 02467 United
Publication: American Geophysical Union, Fall Meeting 2005,
abstract \#SH21A-02
Publication Date: 12/2005
Origin: AGU
AGU Keywords: 2101 Coronal mass ejections (7513), 2111 Ejecta,
driver gases, and magnetic clouds, 2114 Energetic
particles (7514), 7513 Coronal mass ejections
(2101), 7514 Energetic particles (2114)
Bibliographic Code: 2005AGUFMSH21A..02J
Abstract
The Solar Mass Ejection Imager (SMEI) has observed the inner
heliospheric response in white light from over 200 CMEs. One of these,
on January 20, 2005, produced one of the largest Solar Energetic
Particle events ever recorded. We show SMEI orbital difference images
and the 3D solar wind reconstruction of this well-observed CME, and
demonstrate how we can track its outward motion from approximately 20
deg. from the Sun until it vanishes in the SMEI field of view in the
direction of the Ulysses spacecraft. Our 3D reconstruction technique is
used to obtain perspective views from outward-flowing solar wind as
observed from Earth by iteratively fitting a kinematic solar wind
density model using the SMEI white light observations. This 3D modeling
technique permits us to separate the heliospheric response in SMEI from
background noise, and to estimate the 3D structure and transient
heliospheric components of the CME and its speed and mass. We then
determine the total energy of the CME that can be used as input to
determine the total energy output of the event. More information about
the spatial extent and energetics of this CME event can be determined
by measurements in-situ from the Ulysses spacecraft that was beyond 5 AU
and about 35 degrees west of Earth. Ulysses first detected an extremely
fast CME response at the spacecraft 7 days following the event on the
Sun and the transient flow continued for several days. The SMEI 3D
reconstruction shows the event as it passes Earth to the west and helps
to disentangle the CME structure. This will allow a better
understanding of which portions of the CME intersect Ulysses, and the 3D
trajectories of several CMEs observed earlier in coronagraph and SMEI
data.
Title: Comparison of Outputs From an Arctic Sea Ice Snow
Melt Onset Date Algorithm Run for Brightness
Temperature Data Sets From AMSR-E and SSM/I Sensors.
Authors: Jackson, B. A.; Molthan, A.; Anderson, M. R.
Affiliation: AA(University of Nebraska - Lincoln, 214 Bessey Hall
PO Box 880340, Lincoln, NE 68588 United States;
Nebraska - Lincoln, 214 Bessey Hall PO Box 880340,
Lincoln, NE 68588 United States;
- Lincoln, 214 Bessey Hall PO Box 880340, Lincoln,
Publication: American Geophysical Union, Fall Meeting 2005,
abstract \#C33B-1135
Publication Date: 12/2005
Origin: AGU
AGU Keywords: 0700 CRYOSPHERE (4540), 0750 Sea ice (4540), 0758
Remote sensing
Abstract Copyright: (c) 2005: American Geophysical Union
Bibliographic Code: 2005AGUFM.C33B1135J
Abstract
The Advanced Microwave Scanning Radiometer for EOS (AMSR-E) is the
newest conically scanning passive microwave sensor. The AMSR-E was
launched in 2002 with notable advances in technology from previous
sensors like the Special Sensor Microwave Imager (SSM/I). Data from
SSM/I sensors, first launched in 1987, have enabled analysis of
geophysical parameters in the cryosphere for a considerable length of
time. Usage of geophysical parameters derived from brightness
temperature (Tb) data sets from the AMSR-E and SSM/I sensors is expected
to continue for the foreseeable future, so comparisons between the two
sensors are beneficial. Also, the formation of multiple year data sets
allows for climate studies. The AMSR-E and SSM/I both have cryospheric
data presented in a 25 km resolution polar stereographic grid. The
AMSR-E also has a 12.5 km resolution grid. This study will use the
Advanced Horizontal Range Algorithm (AHRA), which computes snow melt
onset dates (SMOD) over Arctic sea ice by flagging changes in the Tb's
during melt due to moisture formation in snow crystals which leads to
an increase in crystalline size. Comparison tests between the AMSR-E
and SSM/I are performed for the melt seasons of 2003 and 2004. One test
compares Tb's and SMOD from the 25 km AMSR-E and 25 km SSM/I Tb data
sets. The other test compares the Tb's and SMOD from the 25 km and 12.5
km grids of the AMSR-E. Both tests will compare individual pixels and
sub-regions of the Arctic between the two data sets by using simple
statistical methods.
Title: Variations in melt conditions in the Arctic through
use of surface energy proxy
Authors: Anderson, M. R.; Jackson, B. A.
Affiliation: AA(University of Nebraska - Lincoln, 214 Bessey
Hall, Lincoln, NE 68588-0340 United States;
214 Bessey Hall, Lincoln, NE 68588-0340 United
Publication: American Geophysical Union, Fall Meeting 2005,
abstract \#C33B-1125
Publication Date: 12/2005
Origin: AGU
AGU Keywords: 0700 CRYOSPHERE (4540), 0740 Snowmelt, 0750 Sea ice
(4540), 0758 Remote sensing, 0764 Energy balance
Abstract Copyright: (c) 2005: American Geophysical Union
Bibliographic Code: 2005AGUFM.C33B1125A
Abstract
The Arctic Ocean is an integral part of the global climate system and an
area that is forecasted to exhibit seasonal fluctuations due to climate
change. This study investigates changes in the Arctic sea ice cover from
1979 to 2004 through a surface energy budget proxy, melting degree days
(MDD). The MDD is calculated from NCEP/NCAR reanalysis temperature
records between the date of melt onset and the ice reduction date. The
ice reduction date is when the ice concentration drops below 80 percent.
Both the melt onset and ice reduction dates are derived from passive
microwave remote sensing. There is a notable period of time, delta t,
between the melt onset and ice reduction. Analysis of delta t for the
Arctic over the microwave record provides explanations for changes in
sea ice cover over time. For instance, an anomalously short delta t
could be an outcome of an atmospheric pattern that brings unseasonably
warm temperatures to the region, reducing the ice concentrations.
However, the same delta t could be a result of thinner ice melting in
the same time period with less warm air advection. Understanding the
surface energy budget could be used to determine why patterns in ice
concentration and extent occur during certain years, but not for others.
Therefore, the MDD is used as a proxy to the amount of energy available
for melt. Variations in the MDD are given for the region to explain
recent changes in the ice conditions.
Title: 3D CME Mass and Energy From Solar Mass Ejection
Imager (SMEI) and Interplanetary Scintillation (IPS)
Data
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.; Yu, Y.
Affiliation: AA(CASS/UCSD), AB(CASS/UCSD), AC(CASS/UCSD),
AD(CASS/UCSD)
Publication: American Astronomical Society Meeting 207, \#111.08;
Bulletin of the American Astronomical Society, Vol.
37, p.1342
Publication Date: 12/2005
Origin: AAS
Bibliographic Code: 2005AAS...20711108J
Abstract
White-light Thomson scattering observations from the Solar Mass Ejection
Imager (SMEI) have recorded the inner heliospheric response to several
hundred CMEs including the halo CMEs of May 28, 2003 and October 28,
2003, and numerous other heliospheric structures. We show the extent of
several well-observed CMEs in SMEI observations, and measure these
events from their first observations in SMEI approximately 20 degrees
from the solar disk until they vanish in the SMEI field of view. Several
portions of large CMEs can be observed in the interplanetary medium
associated with the initial coronal response and the underlying erupting
prominence structure observed by the LASCO coronagraphs and other
instruments. To enhance the images and understand the outward
propagation of these structures we use a 3D reconstruction technique
that obtains perspective views from outward-flowing solar wind as
observed from Earth, iteratively fitting a kinematic solar wind density
model to the SMEI white light observations and, when available, also to
the Solar-Terrestrial Environment Laboratory (STELab), Japan
interplanetary scintillation (IPS) velocity data. This 3D modeling
technique allows separating the heliospheric response in SMEI from
background noise, and estimating the 3D structure of the CME and its
mass. Pixel-to-pixel 3D comparison with the IPS velocity structure gives
the outward flow kinetic energy for these events.
Title: Fabrication of extreme aspect ratio wires within
photonic crystal fibers
Authors: Badding, J. V.; Sazio, P. J. A.; Amezcua Correa, A.;
Scheidemantel, T. J.; Finlayson, C. E.; Baril, N. F.;
Won, D.-J.; Fang, H.; Jackson, B.; Borhan, A.;
Gopalan, V.
Affiliation: AA(Pennsylvania State Univ. (USA)), AB(Univ. of
Southampton (United Kingdom)), AC(Univ. of
Southampton (United Kingdom)), AD(Pennsylvania State
Univ. (USA)), AE(Univ. of Southampton (United
Kingdom)), AF(Pennsylvania State Univ. (USA)),
AG(Pennsylvania State Univ. (USA)), AH(Pennsylvania
State Univ. (USA)), AI(Pennsylvania State Univ.
(USA)), AJ(Pennsylvania State Univ. (USA)),
AK(Pennsylvania State Univ. (USA))
Publication: Photonic Crystals and Photonic Crystal Fibers for
Sensing Applications. Edited by Du, Henry H.
Proceedings of the SPIE, Volume 6005, pp. 111-119
(2005).
Publication Date: 11/2005
Origin: SPIE
Abstract Copyright: (c) 2005: SPIE--The International Society for
Optical Engineering. Downloading of the abstract is
permitted for personal use only.
DOI: 10.1117/12.632675
Bibliographic Code: 2005SPIE.6005..111B
Abstract
We have recently fabricated continuous semiconducting micro and
nanowires within the empty spaces of highly ordered microstructured
(e.g., photonic crystal or holey) optical fibers (MOF's). These systems
contain the highest aspect ratio semiconductor micro- and nanowires yet
produced by any method: centimeters long and ~100 nm in diameter. These
structures combine the flexible light guiding capabilities of an optical
fiber with the electronic and optical functionalities of semiconductors
and have many potential applications for in-fiber sensing, including
in-fiber detection, modulation, and generation of light.
Title: Density Estimation via Optimal Segmentation
Authors: Scargle, Jeffrey D.; Jackson, Bradley W.
Affiliation: AA(Science Division, pace SNASA Ames Research
Center), AB(Mathematics Department, San Jose State
University)
Publication: BAYESIAN INFERENCE AND MAXIMUM ENTROPY METHODS IN
SCIENCE AND ENGINEERING: 25th International Workshop
on Bayesian Inference and Maximum Entropy Methods in
Science and Engineering. AIP Conference
Proceedings, Volume 803, pp. 96-103 (2005).
Publication Date: 11/2005
Origin: AIP
Keywords: statistical analysis, optimisation, image
segmentation
Abstract Copyright: (c) 2005: American Institute of Physics
DOI: 10.1063/1.2149784
Bibliographic Code: 2005AIPC..803...96S
Abstract
A simple algorithm finds the partition of a data interval optimizing the
fitness of a model that represents the underlying signal as constant
over the elements of the partition. Using dynamic programming the
exponentially large space of partitions of N data points is implicitly
but exhaustively searched in time O(N2). This paper also
describes an extension to optimal partitions of higher dimensional data
spaces, with application to multivariate signal processing, image
processing, cluster analysis, density estimation in 3-dimensional
redshift surveys, etc. The algorithm finds the exact global optimum,
automatically determines the model order (the number of segments), and
has a convenient real-time mode.
Title: Coronal mass ejection kinematics deduced from white
light (Solar Mass Ejection Imager) and radio
(Wind/WAVES) observations
Authors: Reiner, M. J.; Jackson, B. V.; Webb, D. F.;
Mizuno, D. R.; Kaiser, M. L.; Bougeret, J.-L.
Affiliation: AA(Catholic University of America and NASA Goddard
Space Flight Center, Greenbelt, Maryland, USA);
AB(Center for Astrophysics and Space Sciences,
University of California, San Diego, California,
USA); AC(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA);
AD(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA);
AE(Solar System Exploration Division, NASA Goddard
Space Flight Center, Greenbelt, Maryland, USA);
AF(Observatoire de Paris, Laboratoire d'Etudes
Spatiales et d'Instrumentation en Astrophysique,
Meudon, France)
Publication: Journal of Geophysical Research, Volume 110, Issue
A9, CiteID A09S14
Publication Date: 09/2005
Origin: AGU
AGU Keywords: Interplanetary Physics: Coronal mass ejections
(7513), Interplanetary Physics: Interplanetary
shocks, Radio Science: Remote sensing, Solar
Physics, Astrophysics, and Astronomy: Coronal mass
ejections (2101), Space Plasma Physics: Shock waves
(4455)
DOI: 10.1029/2004JA010943
Bibliographic Code: 2005JGRA..11009S14R
Abstract
White-light and radio observations are combined to deduce the coronal
and interplanetary kinematics of a fast coronal mass ejection (CME) that
was ejected from the Sun at about 1700 UT on 2 November 2003. The CME,
which was associated with an X8.3 solar flare from W56°, was
observed by the Mauna Loa and Solar and Heliospheric Observatory (SOHO)
Large-Angle Spectrometric Coronograph (LASCO) coronagraphs to 14
R$\odot$. The measured plane-of-sky speed of the LASCO CME
was 2600 km s-1. To deduce the kinematics of this CME, we use
the plane-of-sky white light observations from both the Solar Mass
Ejection Imager (SMEI) all-sky camera on board the Coriolis spacecraft
and the SOHO/LASCO coronagraph, as well as the frequency drift rate of
the low-frequency radio data and the results of the radio
direction-finding analysis from the WAVES experiment on the Wind
spacecraft. In agreement with the in situ observations for this event,
we find that both the white light and radio observations indicate that
the CME must have decelerated significantly beginning near the Sun and
continuing well into the interplanetary medium. More specifically, by
requiring self-consistency of all the available remote and in situ data,
together with a simple, but not unreasonable, assumption about the
general characteristic of the CME deceleration, we were able to deduce
the radial speed and distance time profiles for this CME as it
propagated from the Sun to 1 AU. The technique presented here, which is
applicable to mutual SMEI/WAVES CME events, is expected to provide a
more complete description and better quantitative understanding of how
CMEs propagate through interplanetary space, as well as how the radio
emissions, generated by propagating CME/shocks, relate to the shock and
CME. This understanding can potentially lead to more accurate
predictions for the onset times of space weather events, such as those
that were observed during this unique period of intense solar activity.
Title: The SMEI real-time data pipeline: from raw CCD
frames to photometrically accurate full-sky maps
Authors: Hick, P.; Buffington, A.; Jackson, B. V.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA))
Publication: Solar Physics and Space Weather Instrumentation.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 5901, pp. 340-346
(2005).
Publication Date: 08/2005
Origin: SPIE
DOI: 10.1117/12.617996
Bibliographic Code: 2005SPIE.5901..340H
Abstract
The Solar Mass Ejection Imager (SMEI) records a photometric white-light
response of the interplanetary medium from Earth orbit over most of the
sky. We present the techniques required to process the SMEI data in near
real time from the raw CCD images to their final assembly into
photometrically accurate maps of the sky brightness of Thomson scattered
sunlight. Steps in the SMEI data processing include: integration of new
data into the SMEI data base; conditioning to remove from the raw CCD
images an electronic offset (pedestal) and a temperature-dependent dark
current pattern; placement ("indexing") of the CCD images onto a
high-resolution sidereal grid using known spacecraft pointing
information. During the indexing the bulk of high-energy-particle hits
(cosmic rays), space debris inside the field of view, and pixels with a
sudden state change ("flipper pixels") are identified. Once the
high-resolution grid is produced, it is reformatted to a
lower-resolution set of sidereal maps of sky brightness. From these we
remove bright stars, background stars, and a zodiacal cloud model (their
brightnesses are retained as additional data products). The final maps
can be represented in any convenient sky coordinate system, e.g.,
Sun-centered Hammer-Aitoff or "fisheye" projections. Time series at
selected sidereal locations are extracted and processed further to
remove aurorae, variable stars and other unwanted signals. These time
series of the heliospheric Thomson scattering brightness (with a
long-term base removed) are used in 3D tomographic reconstructions.
Title: Interactive visualization of solar mass ejection
imager (SMEI) volumetric data
Authors: Yu, Yang; Hick, P. P.; Jackson, Bernard V.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA))
Publication: Solar Physics and Space Weather Instrumentation.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 5901, pp. 335-339
(2005).
Publication Date: 08/2005
Origin: SPIE
DOI: 10.1117/12.616358
Bibliographic Code: 2005SPIE.5901..335Y
Abstract
We present a volume rendering system developed for the real time
visualization and manipulation of 3D heliospheric volumetric solar wind
density and velocity data obtained from the Solar Mass Ejection Imager
(SMEI) and interplanetary scintillation (IPS) velocities over the same
time period. Our system exploits the capabilities of the VolumePro 1000
board from TeraRecon, Inc., a low-cost 64-bit PCI board capable of
rendering up to a 512-cubed array of volume data in real time at up to
30 frames per second on a standard PC. Many volume-rendering operations
have been implemented with this system such as stereo/perspective views,
animations of time-sequences, and determination of coronal mass ejection
(CME) volumes and masses. In these visualizations we highlight one time
period where a halo CMEs was observed by SMEI to engulf Earth on October
29, 2003. We demonstrate how this system is used to measure the
distribution of structure and provide 3D mass for individual CME
features, including the ejecta associated with the large prominence
viewed moving to the south of Earth following the late October CME.
Comparisons with the IPS velocity volumetric data give pixel by pixel
and total kinetic energies for these events.
Title: Space performance of the multistage labyrinthine
SMEI baffle
Authors: Buffington, Andrew; Jackson, Bernard V.; Hick, P. P.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA))
Publication: Solar Physics and Space Weather Instrumentation.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 5901, pp. 325-334
(2005).
Publication Date: 08/2005
Origin: SPIE
DOI: 10.1117/12.615526
Bibliographic Code: 2005SPIE.5901..325B
Abstract
The Solar Mass Ejection Imager (SMEI) was launched on 6 January 2003,
and shortly thereafter raised to a nearly circular orbit at 840 km.
Three SMEI CCD cameras on the zenith-nadir oriented CORIOLIS spacecraft
cover most of the sky beyond about 20°. from the Sun, each
102-minute orbit. Data from this instrument provide precision
visible-light photometric sky maps. Once starlight and other constant or
slowly varying backgrounds are subtracted, the residue is mostly
sunlight that has been Thomson-scattered from heliospheric electrons.
These maps enable 3-dimensional tomographic reconstruction of
heliospheric density and velocity. This analysis requires 0.1%
photometry and background-light reduction below one S10 (the brightness
equivalent of a 10th magnitude star per square degree). Thus
10-15 of surface-brightness reduction is required relative to
the solar disk. The SMEI labyrinthine baffle provides roughly
10-10 of this reduction; the subsequent optics system
provides the remainder. We analyze data obtained over two years in
space, and evaluate the full system's stray-light rejection performance.
Title: Low resolution three dimensional reconstruction of
CMEs using solar mass ejection imager (SMEI) data
Authors: Jackson, Bernard V.; Buffington, Andrew; Hick, P. P.;
Wang, Cindy X.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA)), AD(Univ. of
California/San Diego (USA))
Publication: Solar Physics and Space Weather Instrumentation.
Edited by Fineschi, Silvano; Viereck, Rodney A.
Proceedings of the SPIE, Volume 5901, pp. 1-12
(2005).
Publication Date: 08/2005
Origin: SPIE
DOI: 10.1117/12.616329
Bibliographic Code: 2005SPIE.5901....1J
Abstract
White-light Thomson scattering observations from the Solar Mass Ejection
Imager (SMEI) have recorded the inner heliospheric response to many
CMEs. Here we detail how we determine the extent of several CME events
in SMEI observations (including those of 28 May 28 and 28 October,
2003). We show how we are able to measure these events from their first
observations as close as 20° from the solar disk until they fade
away in the SMEI 180° field of view. We employ a 3D reconstruction
technique that provides perspective views from outward-flowing solar
wind as observed at Earth. This is accomplished by iteratively fitting
the parameters of a kinematic solar wind density model to the SMEI white
light observations and to Solar-Terrestrial Environment Laboratory
(STELab), interplanetary scintillation (IPS) velocity data. This 3D
modeling technique enables separating the true heliospheric response in
SMEI from background noise, and reconstructing the 3D heliospheric
structure as a function of time. These reconstructions allow both
separation of the 28 October CME from other nearby heliospheric
structure and a determination of its mass. Comparisons with LASCO for
individual CMEs or portions of them allow a detailed view of changes to
the CME shape and mass as they propagate outward.
Title: Very high altitude aurora observations with the
Solar Mass Ejection Imager
Authors: Mizuno, D. R.; Buffington, A.; Cooke, M. P.;
Eyles, C. J.; Hick, P. P.; Holladay, P. E.;
Jackson, B. V.; Johnston, J. C.; Kuchar, T. A.;
Mozer, J. B.; Price, S. D.; Radick, R. R.;
Simnett, G. M.; Sinclair, D.; Tappin, S. J.;
Webb, D. F.
Affiliation: AA(Institute for Scientific Research, Boston
College, Chestnut Hill, Massachusetts, USA);
AB(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AC(School of Physics and
Astronomy, University of Birmingham, Birmingham,
UK); AD(School of Physics and Astronomy, University
of Birmingham, Birmingham, UK); AE(Center for
Astrophysics and Space Sciences, University of
California, San Diego, La Jolla, California, USA);
AF(Air Force Research Laboratory, Space Vehicles
Directorate, Hanscom Air Force Base, Massachusetts,
USA); AG(Center for Astrophysics and Space Sciences,
University of California, San Diego, La Jolla,
California, USA); AH(Air Force Research Laboratory,
Space Vehicles Directorate, Hanscom Air Force Base,
Massachusetts, USA); AI(Institute for Scientific
Research, Boston College, Chestnut Hill,
Massachusetts, USA); AJ(Air Force Research
Laboratory, Space Vehicles Directorate, Hanscom Air
Force Base, Massachusetts, USA); AK(Air Force
Research Laboratory, Space Vehicles Directorate,
Hanscom Air Force Base, Massachusetts, USA); AL(Air
Force Research Laboratory, Space Vehicles
Directorate, Hanscom Air Force Base, Massachusetts,
USA); AM(School of Physics and Astronomy, University
of Birmingham, Birmingham, UK); AN(Air Force
Research Laboratory, Space Vehicles Directorate,
Hanscom Air Force Base, Massachusetts, USA);
AO(School of Physics and Astronomy, University of
Birmingham, Birmingham, UK); AP(Institute for
Scientific Research, Boston College, Chestnut Hill,
Massachusetts, USA)
Publication: Journal of Geophysical Research, Volume 110, Issue
A7, CiteID A07230
Publication Date: 07/2005
Origin: AGU
AGU Keywords: Atmospheric Composition and Structure: Airglow and
aurora, Magnetospheric Physics: Auroral phenomena
(2407), Ionosphere: Polar cap ionosphere,
Ionosphere: Auroral ionosphere (2704), Ionosphere:
Topside ionosphere
DOI: 10.1029/2004JA010689
Bibliographic Code: 2005JGRA..11007230M
Abstract
The Solar Mass Ejection Imager (SMEI) is a sensitive scanning instrument
mounted on the Coriolis satellite that assembles an approximately
all-sky image of the heliosphere in red-biased visible light once per
orbit. Its lines of sight pass obliquely through the topside ionosphere
and magnetosphere. We present serendipitous observations of a visual
phenomenon detected at high altitudes (>=840 km) over the auroral
zones and polar caps. The phenomenon is observed in two basic forms. The
first, and more common, are periods of brief (1-3 min), nearly uniform
illumination of the imager's field of view, which we interpret as
transits of the satellite through a luminous medium. The second appear
as localized filamentary structures, which we interpret as columns of
luminous material, viewed from a distance, possibly extending to visible
altitudes of 2000 km or higher. More than 1000 occurrences of these
phenomena were recorded during the first full year of operations. These
observations are well correlated in brightness and frequency with
periods of enhanced geomagnetic activity.
Title: Niobium titanium nitride-based
superconductor-insulator-superconductor mixers for
low-noise terahertz receivers
Authors: Jackson, B. D.; de Lange, G.; Zijlstra, T.;
Kroug, M.; Klapwijk, T. M.; Stern, J. A.
Affiliation: AA(SRON Netherlands Institute for Space Research,
Landleven 12, 9747 AD Groningen, The Netherlands),
AB(SRON Netherlands Institute for Space Research,
Landleven 12, 9747 AD Groningen, The Netherlands),
AC(Kavli Institute for Nanoscience, Faculty of
Applied Sciences, Delft University of Technology,
Lorentzweg 1, 2628 CJ Delft, The Netherlands),
AD(Kavli Institute for Nanoscience, Faculty of
Applied Sciences, Delft University of Technology,
Lorentzweg 1, 2628 CJ Delft, The Netherlands),
AE(Kavli Institute for Nanoscience, Faculty of
Applied Sciences, Delft University of Technology,
Lorentzweg 1, 2628 CJ Delft, The Netherlands),
AF(Jet Propulsion Laboratory, California Institute
of Technology, 4800 Oak Grove Drive, Pasadena,
California 91109)
Publication: Journal of Applied Physics, Volume 97, Issue 11, pp.
113904-113904-8 (2005).
Publication Date: 06/2005
Origin: AIP
Keywords: niobium compounds, titanium compounds, niobium, type
II superconductors,
superconductor-insulator-superconductor mixers,
submillimetre wave receivers, superconducting
microwave devices, superconducting integrated
circuits
Abstract Copyright: (c) 2005: American Institute of Physics
DOI: 10.1063/1.1927281
Bibliographic Code: 2005JAP....97k3904J
Abstract
Integrating NbTiN-based microstrip tuning circuits with traditional Nb
superconductor-insulator-superconductor (SIS) junctions enables the
low-noise operation regime of SIS mixers to be extended from below 0.7
to 1.15 THz. In particular, mixers incorporating a
NbTiN/SiO2/NbTiN microstrip tuning circuit offer low-noise
performance below 0.8-0.85 THz, although their sensitivities drop
significantly at higher frequencies. Furthermore, a microstrip geometry
in which NbTiN is used as the ground plane material only
(NbTiN/SiO2/Al) yields significant improvements in the
sensitivities of SIS mixers operating up to 1.15 THz, with an upper
operating frequency that depends upon the quality of the NbTiN layer,
and thus its deposition process. Films deposited at room temperature
have Tc=14.4 K and rhon,20 K~60 muOmega cm, and offer
low-noise performance up to 1 THz, whereas films deposited at 400 °C
have Tc=16 K and rhon,20 K~110 muOmega cm, and offer
low-noise performance up to 1.15 THz. Taken together, these results
demonstrate that the high-frequency surface resistance of a NbTiN layer
depends upon the film's structural properties. Most significantly, the
drop in performance that is seen at F>1 THz in mixers incorporating
NbTiN ground planes deposited at room temperature is attributed to
nonhomogeneities in the structural and electrical properties of these
films, as is the poor performance of mixers that incorporate NbTiN
wiring layers at F>0.85 THz. The development of these NbTiN-based
microstrip tuning circuits will enable the production of low-noise SIS
mixers for the 0.8-0.96- and 0.96-1.12-THz frequency bands of the
Heterodyne Instrument for the Far Infrared on board the European Space
Agency's Herschel Space Observatory.
Title: The band 3 and 4 Flight Model mixer units for HIFI
Authors: de Lange, G.; Jackson, B. D.; Jochemsen, M.;
Eggens, M.; Golstein, H.; Laauwen, W. M.;
de Jong, L.; Kikken, S.; Pieters, C.; Smit, H.;
van Nguyen, D.; Zijlstra, T.; Kroug, M.;
Klapwijk, T. M.
Publication: Sixteenth International Symposium on Space Terahertz
Technology, held May 2-4, 2005 at Chalmers
University of Technology. Göteborg, Sweden., p.449
Publication Date: 05/2005
Origin: ADS
Bibliographic Code: 2005stt..conf..449D
Abstract
Not Available
Title: Design and development of a 600-720 GHz receiver
cartridge for ALMA Band 9
Authors: Hesper, R.; Jackson, B. D.; Baryshev, A. M.;
Adema, J.; Wielinga, K.; Kroug, M.; Zijlstra, T.;
Gerlofsma, G.; Bekema, M.; Keizer, K.; Schaeffer, H.;
Barkhof, J.; Mena, F. P.; Koops, A.; Rivas, R.;
Klapwijk, T. M.; Wild, W.
Publication: Sixteenth International Symposium on Space Terahertz
Technology, held May 2-4, 2005 at Chalmers
University of Technology. Göteborg, Sweden.,
p.110-115
Publication Date: 05/2005
Origin: ADS
Bibliographic Code: 2005stt..conf..110H
Abstract
Not Available
Title: Terahertz Technology for ESPRIT - A Far-Infrared
Space Interferometer
Authors: Wild, W.; de Graauw, Th.; Baryshev, A.;
Baselmans, J.; Gao, J. R.; Helmich, F.;
Jackson, B. D.; Koshelets, V. P.; Roelfsema, P.;
Whyborn, N. D.; Yagoubov, P.
Publication: Sixteenth International Symposium on Space Terahertz
Technology, held May 2-4, 2005 at Chalmers
University of Technology. Göteborg, Sweden.,
p.68-74
Publication Date: 05/2005
Origin: ADS
Bibliographic Code: 2005stt..conf...68W
Abstract
Not Available
Title: Application of Synchrotron X-Ray Microbeam
Spectroscopy to the Determination of Metal
Distribution and Speciation in Biological Tissues
Authors: Punshon, T.; Jackson, B. P.; Lanzirotti, A.;
Hopkins, W. A.; Bertsch, P. M.; Burger, J.
Publication: Spectroscopy Letters, vol. 38, issue 3, pp. 343-363
Publication Date: 05/2005
Origin: CROSSREF
DOI: 10.1081/SL-200058715
Bibliographic Code: 2005SpecL..38..343P
Abstract
Not Available
Title: NbTiN-based THz SIS mixers for the Herschel Space
Observatory
Authors: Jackson, Brian D.
Affiliation: Technische Universiteit Delft, The Netherlands
Publication Date: 05/2005
Origin: AUTHOR
Bibliographic Code: 2005PhDT........37J
Abstract
Not Available
Title: Preliminary Three Dimensional CME Mass and Energy
Using Solar Mass Ejection Imager (SMEI) Data
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.; Yu, Y.;
Webb, D.; Mizuno, D.; Kuchar, T.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AB(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AC(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
for Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Chestnut Hill, MA 01731 United States;
College, Chestnut Hill, MA 01731 United States;
College, Chestnut Hill, MA 01731 United States;
Publication: American Geophysical Union, Spring Meeting 2005,
abstract \#SP44A-05
Publication Date: 05/2005
Origin: AGU
AGU Keywords: 2111 Ejecta, driver gases, and magnetic clouds, 2164
Solar wind plasma, 2194 Instruments and techniques,
7513 Coronal mass ejections, 7594 Instruments and
techniques
Bibliographic Code: 2005AGUSMSP44A..05J
Abstract
White-light Thomson scattering observations from the Solar Mass Ejection
Imager (SMEI) have recorded the inner heliospheric response to several
hundred CMEs including the May 28, 2003 halo CME, the October 28, 2003
halo CME, and numerous other heliospheric structures. Here we show the
extent of several well-observed CMEs in SMEI observations, and show how
we are able to track events from their first measurements in SMEI
approximately 20° from the solar disk until they vanish from the
SMEI 180° field of view. Several portions of large CMEs observed by
the LASCO coronagraphs can be tracked into the interplanetary medium
associated with the initial CME response and the underlying erupting
prominence structure. We use a 3D reconstruction technique that obtains
perspective views from outward-flowing solar wind as observed from
Earth, iteratively fitting a kinematic solar wind density model using
the SMEI white light observations and, when available, the
Solar-Terrestrial Environment Laboratory (STELab), Japan interplanetary
scintillation (IPS) velocity data. This 3D modeling technique allows us
to separate the heliospheric response in SMEI from background noise, and
to estimate the 3D structure of the CME and its mass. For instance, the
analysis shows and tracks outward the northward portion of the loop
structure of the October 28, 2003 CME observed as a halo in LASCO images
that passes Earth on October 29. We determine an excess mass for this
structure of 6.7×1016g and a total mass including an ambient
background of 8.3×1016g. The very fast structure compared in a 3D
pixel to pixel comparison with the IPS velocity data gives a kinetic
energy for the northward portion of this event of 2.0×1034erg as
it passes Earth.
Title: Comparative Analyses of the CSSS Calculation in the
UCSD Tomographic Solar Observations
Authors: Dunn, T.; Jackson, B. V.; Hick, P. P.;
Buffington, A.; Zhao, X. P.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego), AB(Center
for Astrophysics and Space Sciences, University of
California at San Diego), AC(Center for Astrophysics
and Space Sciences, University of California at San
Diego), AD(Center for Astrophysics and Space
Sciences, University of California at San Diego),
AE(W.W. Hansen Experimental Physics Laboratory,
Stanford University)
Publication: Solar Physics, Volume 227, Issue 2, pp.339-353
Publication Date: 04/2005
Origin: SPRINGER
DOI: 10.1007/s11207-005-2759-x
Bibliographic Code: 2005SoPh..227..339D
Abstract
We describe a new method to derive the interplanetary magnetic field
(IMF) out to 1 AU from photospheric magnetic field measurements. The
method uses photospheric magnetograms to calculate a source surface
magnetic field at 15Ro. Specifically, we use Wilcox
Solar Observatory (WSO) magnetograms as input for the Stanford
Current-Sheet Source-Surface (CSSS) model. Beyond the source surface the
magnetic field is convected along velocity flow lines derived by a
tomographic technique developed at UCSD and applied to interplanetary
scintillation (IPS) observations. We compare the results with in situ
data smoothed by an 18-h running mean. Radial and tangential magnetic
field amplitudes fit well for the 20 Carrington rotations studied, which
are largely from the active phase of the solar cycle. We show exemplary
results for Carrington rotation 1965, which includes the Bastille Day
event.
Title: A drug is effective if better than a harmless
control
Authors: Jackson, Brooks; Fleming, Thomas
Publication: Nature, Volume 434, Issue 7037, pp. 1067 (2005).
Publication Date: 04/2005
Origin: NATURE
Abstract Copyright: (c) 2005: Nature
DOI: 10.1038/4341067a
Bibliographic Code: 2005Natur.434.1067J
Abstract
Valid trials can still be held, as with HIVNET 012, when ethics rules
out a placebo group.
Title: Meta-Fibonacci Sequences, Binary Trees, and Extremal
Compact Codes
Authors: Jackson, Brad; Ruskey, Frank
Publication: eprint arXiv:math/0504400
Publication Date: 04/2005
Origin: ARXIV
Keywords: Combinatorics, 05A15, 11B39
Comment: 13 pages, 3 figures
Bibliographic Code: 2005math......4400J
Abstract
We look at a family of meta-Fibonacci sequences which arise in studying
the number of leaves at the largest level in certain infinite sequences
of binary trees, restricted compositions of an integer, and binary
compact codes. For this family of meta-Fibonacci sequences and two
families of related sequences we derive ordinary generating functions
and recurrence relations. Included in these families of sequences are
several well-known sequences in the Online Encyclopedia of Integer
Sequences (OEIS).
Title: Bombardment of Ni(100) surface with low-energy
argons: molecular dynamics simulations
Authors: Guvenc, Z.; Hippler, R.; Jackson, B.
Publication: Thin Solid Films, vol. 474, issue 1-2, pp. 346-357
Publication Date: 03/2005
Origin: CROSSREF
DOI: 10.1016/j.tsf.2004.09.023
Bibliographic Code: 2005TSF...474..346G
Abstract
Not Available
Title: Oscillations of a Bose-Einstein Condensate Rotating
in a Harmonic Plus Quartic Trap
Authors: Cozzini, M.; Fetter, A. L.; Jackson, B.;
Stringari, S.
Affiliation: Dipartimento di Fisica, Università di Trento and
BEC-INFM, I-38050 Povo, Italy
Publication: Physical Review Letters, vol. 94, Issue 10, id.
100402
Publication Date: 03/2005
Origin: APS
Abstract Copyright: (c) 2005: The American Physical Society
DOI: 10.1103/PhysRevLett.94.100402
Bibliographic Code: 2005PhRvL..94j0402C
Abstract
We study the normal modes of a two-dimensional rotating Bose-Einstein
condensate confined in a quadratic plus quartic trap. Hydrodynamic
theory and sum rules are used to derive analytical predictions for the
collective frequencies in the limit of high angular velocities Omega
where the vortex lattice produced by the rotation exhibits an annular
structure. We predict a class of excitations with frequency
&surd;(6)Omega in the rotating frame, irrespective of the mode
multipolarity m, as well as a class of low energy modes with frequency
proportional to |m|/Omega. The predictions are in good agreement with
results of numerical simulations based on the 2D Gross-Pitaevskii
equation. The same analysis is also carried out at even higher angular
velocities, where the system enters the giant vortex regime.
Title: Quasiclassical study of Eley-Rideal and hot atom
reactions of H atoms with Cl adsorbed on a Au(111)
surface
Authors: Quattrucci, Joseph G.; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003
Publication: Journal of Chemical Physics, Volume 122, Issue 7,
pp. 074705-074705-13 (2005).
Publication Date: 02/2005
Origin: AIP
Keywords: atom-surface impact, adsorbed layers, hydrogen
neutral atoms, chlorine, gold, potential energy
surfaces, rotational states, translational states,
radiochemistry, surface chemistry, reaction kinetics
theory, excited states, atom-atom collisions
Abstract Copyright: (c) 2005: American Institute of Physics
DOI: 10.1063/1.1851498
Bibliographic Code: 2005JChPh.122g4705Q
Abstract
Using quasiclassical methods and a potential energy surface based on
total energy calculations, we have found that H atoms react with Cl
atoms adsorbed onto a Au(111) surface to produce HCl via Eley-Rideal
(ER), hot atom (HA), and Langmuir-Hinschelwood (LH) pathways. We observe
two ER mechanisms. At small normal incidence energies reaction results
from a more or less direct collision with Cl, leading to a large amount
of product vibration (nu=8), and relatively cold rotation and
translation. In the second mechanism, more dominant at near-normal
incidence and/or large incident energies, the H atom passes near Cl,
recoils from the metal, and is pulled into orbit about Cl. This leads to
broader product state distributions, and a more even distribution of the
3.0 eV of available energy among the product degrees of freedom, similar
to products formed via the HA pathway. Overall, ER processes tend to
contribute less than 10% to the reactivity, and most of the HCl is
formed via HA processes. There is an increase in HCl formation with
surface temperature for both the ER and HA mechanisms, but this increase
is relatively weak. We observe typically about 12% H atom sticking,
which would lead to HCl formation via a LH process in the experiments,
above 140 K. We observe a weak forward scattering due to the direct ER
component, as in the experiments. However, unlike the experiments, we
observe a dip in our product angular distributions about
thetaf=0°, which we ascribe to our quasiclassical
approximation. While we tend to see more energy in the hot products than
in the experiments, our product translational, rotational, and
vibrational distributions are in relatively reasonable agreement with
those measured. One major disagreement with experiment is that there is
apparently a significant sticking of the H atom at low temperatures,
leading to a large LH component. In addition, the ER and HA components
increase much more strongly with temperature than in the calculations.
It is possible that electon-hole pair excitations in the metal strongly
relax both the H atom and the excited HCl molecules formed.
Title: An algorithm for optimal partitioning of data on an
interval
Authors: Jackson, B.; Scargle, J. D.; Barnes, D.; Arabhi, S.;
Alt, A.;
Publication: IEEE Signal Processing Letters, vol. 12, issue 2,
pp. 105-108
Publication Date: 02/2005
Origin: ioumousis, P.; Gwin, E.; San, P.; Tan, L.; Tsai, Tun
Tao
DOI: 10.1109/LSP.2001.838216
Bibliographic Code: 2005ISPL...12..105J
Abstract
Not Available
Title: Rapid rotation of a Bose-Einstein condensate in a
harmonic plus quartic trap
Authors: Fetter, Alexander L.; Jackson, B.; Stringari, S.
Affiliation: AA(Geballe Laboratory for Advanced Materials and
Department of Physics and Department of Applied
Physics, Stanford University, Stanford, California
94305-4045, USA), AB(Dipartimento di Fisica,
Università di Trento and BEC-INFM, I-38050 Povo,
Italy), AC(Dipartimento di Fisica, Università di
Trento and BEC-INFM, I-38050 Povo, Italy; Geballe
Laboratory for Advanced Materials and Department of
Physics and Department of Applied Physics, Stanford
University, Stanford, California 94305-4045, USA)
Publication: Physical Review A, vol. 71, Issue 1, id. 013605
Publication Date: 01/2005
Origin: APS
Abstract Copyright: (c) 2005: The American Physical Society
DOI: 10.1103/PhysRevA.71.013605
Bibliographic Code: 2005PhRvA..71a3605F
Abstract
A two-dimensional rapidly rotating Bose-Einstein condensate in an
anharmonic trap with quadratic and quartic radial confinement is studied
analytically with the Thomas-Fermi approximation and numerically with
the full time-independent Gross-Pitaevskii equation. The quartic trap
potential allows the rotation speed Omega to exceed the radial
harmonic frequency omega⊥ . In the regime
Omega≳omega⊥ , the condensate contains a dense
vortex array (approximated as solid-body rotation for the analytical
studies). At a critical angular velocity Omegah , a
central hole appears in the condensate. Numerical studies confirm the
predicted value of Omegah , even for interaction
parameters that are not in the Thomas-Fermi limit. The behavior is also
investigated at larger angular velocities, where the system is expected
to undergo a transition to a giant vortex (with pure irrotational flow).
Title: Quantum studies of H atom trapping on a graphite
surface
Authors: Sha, Xianwei; Jackson, Bret; Lemoine, Didier;
Lepetit, Bruno
Affiliation: AA(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003),
AB(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003),
AC(Laboratoire Collisions, Agrégats, Réactivité, UMR
CNRS 5589, Institut de Recherche sur les Systèmes
Atomiques et Moléculaires Complexes, Université Paul
Sabatier, Bâtiment 3R1B4, 31062 Toulouse Cedex 4,
France), AD(Laboratoire Collisions, Agrégats,
Réactivité, UMR CNRS 5589, Institut de Recherche sur
les Systèmes Atomiques et Moléculaires Complexes,
Université Paul Sabatier, Bâtiment 3R1B4, 31062
Toulouse Cedex 4, France)
Publication: Journal of Chemical Physics, Volume 122, Issue 1,
pp. 014709-014709-8 (2005).
Publication Date: 01/2005
Origin: AIP
Keywords: hydrogen, isotope effects, deuterium, graphite,
chemisorption, potential energy surfaces, density
functional theory, atom-surface impact, eigenvalues
and eigenfunctions, bonds (chemical)
Abstract Copyright: (c) 2005: American Institute of Physics.
DOI: 10.1063/1.1827601
Bibliographic Code: 2005JChPh.122a4709S
Abstract
The trapping and sticking of H and D atoms on the graphite (0001)
surface is examined, over the energy range of 0.1-0.9 eV. For hydrogen
to chemisorb onto graphite, the bonding carbon must pucker out of the
surface plane by several tenths of an angstrom. A quantum approach in
which both the hydrogen and the bonding carbon atoms can move is used to
model the trapping, and a potential energy surface based on density
functional theory calculations is employed. It is found, for energies
not too far above the 0.2 eV barrier to chemisorption that a significant
fraction of the incident H or D atoms can trap. The forces on the
bonding carbon are large, and it can reconstruct within 50 fs or so.
After about 100 fs, most of the trapped H atoms scatter back into the
gas phase, but the 5%-10% that remain can have lifetimes on the order of
a picosecond or more. Calculations of the resonance eigenstates and
lifetimes confirm this. An additional lattice degree of freedom is
included quantum mechanically and is shown to significantly increase the
amount of H that remains trapped after 1 ps. Further increasing the
incident energy destabilizes the trapped state, leading to less H
remaining trapped at long times. We estimate that for a full dissipative
bath, the sticking probabilities should be on the order of 0.1.
Title: Exploratory submm space radio-interferometric
telescope
Authors: de Graauw, Th.; Helmich, F. P.; Cernicharo, J.;
Wild, W.; Baryshev, A.; Bos, A.; den Herder, J.-W.;
Gunst, A.; Jackson, B.; van Langevelde, H. J.;
Maat, P.; Martin-Pintado, J.; Noordam, J.;
Quirrenbach, A.; Roelfsema, P. R.; Venema, L.;
Wesselius, P. R.; Yagoubov, P.
Affiliation: AA(SRON Netherlands Institute for Space Research,
Landleven 12, 9747 AD Groningen, The Netherlands;
Kapteyn Astronomical Institute, P.O. Box 800, 9700
AV Groningen, The Netherlands), AB(SRON Netherlands
Institute for Space Research, Landleven 12, 9747 AD
Groningen, The Netherlands; Kapteyn Astronomical
Institute, P.O. Box 800, 9700 AV Groningen, The
Netherlands), AC(CSIC, Madrid, C/Serrano 113-121,
28006 Madrid, Spain), AD(SRON Netherlands Institute
for Space Research, Landleven 12, 9747 AD Groningen,
The Netherlands; Kapteyn Astronomical Institute,
P.O. Box 800, 9700 AV Groningen, The Netherlands),
AE(Kapteyn Astronomical Institute, P.O. Box 800,
9700 AV Groningen, The Netherlands), AF(ASTRON,
Dwingeloo, P.O. Box 2, 7990 AA, Dwingeloo, The
Netherlands), AG(SRON Netherlands Institute for
Space Research, Landleven 12, 9747 AD Groningen, The
Netherlands), AH(ASTRON, Dwingeloo, P.O. Box 2, 7990
AA, Dwingeloo, The Netherlands), AI(SRON Netherlands
Institute for Space Research, Landleven 12, 9747 AD
Groningen, The Netherlands), AJ(Joint Institute for
VLBI in Europe, P.O. Box 2, 7990 AA, Dwingeloo, The
Netherlands), AK(ASTRON, Dwingeloo, P.O. Box 2, 7990
AA, Dwingeloo, The Netherlands), AL(CSIC, Madrid,
C/Serrano 113-121, 28006 Madrid, Spain), AM(ASTRON,
Dwingeloo, P.O. Box 2, 7990 AA, Dwingeloo, The
Netherlands), AN(Leiden Observatory, P.O. Box 9513,
2300 RA Leiden, The Netherlands), AO(SRON
Netherlands Institute for Space Research, Landleven
12, 9747 AD Groningen, The Netherlands; Kapteyn
Astronomical Institute, P.O. Box 800, 9700 AV
Groningen, The Netherlands), AP(ASTRON, Dwingeloo,
P.O. Box 2, 7990 AA, Dwingeloo, The Netherlands),
AQ(SRON Netherlands Institute for Space Research,
Landleven 12, 9747 AD Groningen, The Netherlands;
Kapteyn Astronomical Institute, P.O. Box 800, 9700
AV Groningen, The Netherlands), AR(SRON Netherlands
Institute for Space Research, Landleven 12, 9747 AD
Groningen, The Netherlands)
Publication: Advances in Space Research, Volume 36, Issue 6, p.
1109-1113.
Publication Date: 00/2005
Origin: ELSEVIER
DOI: 10.1016/j.asr.2005.06.053
Bibliographic Code: 2005AdSpR..36.1109D
Abstract
Angular resolution in the far-infrared (FIR) wavelength regime limits
the range of size scales accessible although the FIR range has become of
prime importance for astrophysics. Observations of ionic, atomic and
molecular lines, many of them only present in the FIR spectral region,
provide important and unique information on the star- and planet
formation process occurring in interstellar clouds, and more generally
on the lifecycle of gas and dust. All these regions are heavily obscured
by dust, and (F)IR spectroscopic observations are important means of
gaining insight about their physical and chemical environments, and the
evolutionary development. Besides the high spectral resolution these
investigations require high angular resolution in order to match the
small angular sizes of star forming cores and circumstellar disks. The
European Space Agency's (ESA) Herschel satellite will provide the
first step towards high spectral resolution. To obtain both high
spectral and spatial resolution capabilities, we propose a heterodyne
aperture-synthesis mission concept, ESPRIT, to operate in a wavelength
regime that is neither accessible from the ground by Atacama Large
Millimeter Array (ALMA), nor with James Webb Space Telescope (JWST).
Title: The European Receivers for ALMA
Authors: Tan, G. H.; Jackson, B. D.; Lazareff, B.; Adema, J.;
Baryshev, A. M.; Hesper, R.; Klapwijk, T. M.;
Kroug, M.; Mahieu, S.; Maier, D.; Schuster, K.;
Wielinga, K.; Zijlstra, T.
Affiliation: AA(EUROPEAN SOUTHERN OBSERVATORY) AB(NETHERLANDS
RESEARCH SCHOOL FOR ASTRONOMY (NOVA), LEIDEN, THE
NETHERLANDS & SRON NATIONAL INSTITUTE FOR SPACE
RESEARCH, GRONINGEN, THE NETHERLANDS) AC(INSTITUT DE
RADIO ASTRONOMIE MILLIMÉTRIQUE (IRAM), GRENOBLE,
FRANCE) AD(NETHERLANDS RESEARCH SCHOOL FOR ASTRONOMY
(NOVA), LEIDEN, THE NETHERLANDS & KAPTEYN INSTITUTE,
UNIVERSITY OF GRONINGEN, THE NETHERLANDS)
AE(NETHERLANDS RESEARCH SCHOOL FOR ASTRONOMY (NOVA),
LEIDEN, THE NETHERLANDS & KAPTEYN INSTITUTE,
UNIVERSITY OF GRONINGEN, THE NETHERLANDS)
AF(NETHERLANDS RESEARCH SCHOOL FOR ASTRONOMY (NOVA),
LEIDEN, THE NETHERLANDS & KAPTEYN INSTITUTE,
UNIVERSITY OF GRONINGEN, THE NETHERLANDS) AG(KAVLI
INSTITUTE OF NANOSCIENCE, DELFT UNIVERSITY OF
TECHNOLOGY, THE NETHERLANDS) AH(KAVLI INSTITUTE OF
NANOSCIENCE, DELFT UNIVERSITY OF TECHNOLOGY, THE
NETHERLANDS) AI(INSTITUT DE RADIO ASTRONOMIE
MILLIMÉTRIQUE (IRAM), GRENOBLE, FRANCE) AJ(INSTITUT
DE RADIO ASTRONOMIE MILLIMÉTRIQUE (IRAM), GRENOBLE,
FRANCE) AK(INSTITUT DE RADIO ASTRONOMIE
MILLIMÉTRIQUE (IRAM), GRENOBLE, FRANCE) AL(MECON
ENGINEERING BV, DOETINCHEM, THE NETHERLANDS)
AM(KAVLI INSTITUTE OF NANOSCIENCE, DELFT UNIVERSITY
OF TECHNOLOGY, THE NETHERLANDS)
Publication: The Messenger (ISSN0722-6691), No.118, p. 18-23
(December 2004)
Publication Date: 12/2004
Origin: AUTHOR; ESO
Bibliographic Code: 2004Msngr.118...18T
Abstract
To a large extent the scientific capabilities of the Atacama Large
Millimeter Array (ALMA) will depend on the receivers mounted on each of
the 64 antennas. In the last year, substantial progress has been made in
the design of these receivers and currently a transition towards
production is underway. Two out of the four initial baseline frequency
bands funded under the bi-lateral project between Europe and North
America are a European responsibility. This European contribution will
be for the shortest wavelength ALMA Bands designated 7 and 9, covering
the frequency ranges 275 GHz to 373 GHz and 602 GHz to 720 GHz.
Title: Understanding Hydrologic Model Uncertainty: A Report
on the IAHS-PUB Workshop
Authors: Meixner, Tom; Gupta, Hoshin; Montanari, Alberto;
Jackson, Bethania
Publication: Eos, Transactions American Geophysical Union, Volume
85, Issue 51, p. 556-556
Publication Date: 12/2004
Origin: AGU
AGU Keywords: Hydrology: Runoff and streamflow, Hydrology:
Instruments and techniques, Meetings
Abstract Copyright: (c) 2004: American Geophysical Union
DOI: 10.1029/2004EO510007
Bibliographic Code: 2004EOSTr..85..556M
Abstract
The current ``Decade on Prediction in Ungauged Basins (PUB)'' initiative
of the International Association of Hydrological Sciences (IAHS) is
targeted at the ``Holy Grail'' of hydrology, i.e., to be able to predict
the ``hydrological'' behavior of any ungauged basin. It seems probable
that this mission cannot be accomplished; that is, we may never be able
to precisely predict discharge at a given location. The treatment of
uncertainty is, therefore, critical to the problem of understanding what
it means to make a prediction in an ungauged basin. This goal is a
fundamental objective for any scientific endeavor: to predict the
unknown. At the heart of the PUB initiative is a commitment to quantify
the uncertainty in hydrologic flux predictions.
Title: Zodiacal Light Analysis and Removal From the Solar
Mass Ejection Imager (SMEI) Data
Authors: Simon, S.; Jackson, B. V.; Buffington, A.;
Hick, P. P.; Smith, A.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
for Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH21A-0398
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 6035 Orbital and rotational dynamics, 6213 Dust,
2129 Interplanetary dust, 2164 Solar wind plasma,
2194 Instruments and techniques
Bibliographic Code: 2004AGUFMSH21A0398S
Abstract
The Solar Mass Ejection Imager (SMEI) experiment provides white-light
photometric maps covering most of the sky each orbit of the Coriolis
spacecraft. The SMEI differential photometry specification is 0.1% for
each 1 square degree sky bin, and was designed to provide precise
photometric white light images over most of the sky on each 102-minute
Earth orbit in order to map heliospheric structures. One of the
brightest contaminant signals observed in SMEI is zodiacal light
brightness that must be modeled and subtracted from the data in order to
provide heliospheric sky maps free from large background changes. We
have devised a technique to remove zodiacal dust brightness from the
SMEI maps, and in order to do so accurately measure the asymmetry of the
equatorial dust to the ecliptic plane as well as the Gegenschein
brightness throughout the year. We present preliminary analyses of
these observations for specific intervals during the one and a half year
lifetime of SMEI.
Title: The Deceleration of Interplanetary Transients
Between the Sun and 5 AU
Authors: Tappin, J.; Simnett, G. M.; Jackson, B. V.
Affiliation: AA(School of Physics and Astronomy, University of
Birmingham, Edgbaston, Birmingham, B15 2TT United
Physics and Astronomy, University of Birmingham,
Edgbaston, Birmingham, B15 2TT United Kingdom;
California, San Diego, Gilman Drive,, San Diego, CA
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH21A-0394
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 7514 Energetic
particles (2114)
Bibliographic Code: 2004AGUFMSH21A0394T
Abstract
During the the SMEI mission, Ulysses has been at relatively low
latitudes (less than 25 degrees) and near aphelion (4.8 to 5.4 AU). This
has provided us with an opportunity to trace interplanetary transient
disturbances from near the Sun (with LASCO), around 1AU with SMEI and
ACE and then again near 5AU with Ulysses. We have selected a number of
events where the identification of the disturbance is clear in LASCO,
SMEI and Ulysses and use the propagation of the disturbance through the
heliosphere to draw conclusions regarding the dynamics of these
disturbances. In particular we focus on the duration of the "driving
flow" and on the significance of "swept-up" matter.
Title: Comparison of Solar Mass Ejection Imager (SMEI)
White Light Observations with IPS Velocity
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.;
Kojima, M.; Tokumaru, M.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AB(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AC(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AD(Solar-Terrestrial Environment Laboratory, Nagoya
University, Toyokawa, 442-8507 Japan;
AE(Solar-Terrestrial Environment Laboratory, Nagoya
University, Toyokawa, 442-8507 Japan;
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH21A-0393
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 7594 Instruments and
techniques, 2102 Corotating streams, 2111 Ejecta,
driver gases, and magnetic clouds, 2164 Solar wind
plasma
Bibliographic Code: 2004AGUFMSH21A0393J
Abstract
The Solar Mass Ejection Imager (SMEI) experiment is fixed to the
Coriolis spacecraft and views the sky above Earth using
sunlight-rejecting baffles and CCD camera technology. SMEI was designed
to provide precise photometric white light images over most of the sky
on each 102-minute Earth orbit. The brightness sky maps of the inner
heliosphere indicate a rich variety of electron density structures that
are produced by the material that propagates through it and its
interaction with ambient structures. We present some of the
preliminary results of the analysis of these photometric SMEI
observations derived by 3D reconstructions that allow contaminant
signal removal using both interplanetary scintillation (IPS) velocities
and SMEI data. We use these analyses to compare preliminary SMEI
tomographic white-light results with IPS velocity for the same time
intervals.
Title: Systematic Error Reduction and Photometric
Calibration for the Solar Mass Ejection Imager
(SMEI)
Authors: Buffington, A.; Jackson, B. V.; Hick, P.
Affiliation: AA(Univ. California San Diego, Center for
Astrophysics and Space Sciences, 9500 Gilman Drive,
La Jolla, CA 92093 United States;
Diego, Center for Astrophysics and Space Sciences,
9500 Gilman Drive, La Jolla, CA 92093 United States
Diego, Center for Astrophysics and Space Sciences,
9500 Gilman Drive, La Jolla, CA 92093 United States
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH11A-07
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 7594 Instruments and
techniques
Bibliographic Code: 2004AGUFMSH11A..07B
Abstract
The Solar Mass Ejection Imager (SMEI) instrument provides white-light
photometric maps covering most of the sky each orbit of the Coriolis
spacecraft. The SMEI differential photometry specification is 0.1% for
each 1 square degree sky bin. A labyrinthine baffle reduces scattered
sunlight, but for a portion of the data a background residue must also
be subtracted to finally reach this specification. We describe this
process, and further discuss how bright stars are used to determine an
appropriate conversion from the CCD-camera data units to sky surface
brightness. Also, the CCD in the camera viewing closest to the Sun
operates significantly warmer than expected, which gives rise to a
changing population of "hot pixels". We describe a data-analysis process
which significantly alleviates the photometric impact of this.
Title: Wind/WAVES and SMEI Observations of ICMEs
Authors: Reiner, M. J.; Jackson, B. V.; Webb, D. F.;
Kaiser, M. L.; Cliver, E. W.; Bougeret, J. L.
Affiliation: AA(Catholic University - NASA/GSFC, Code 690.2,
Greenbelt, MD 20771 United States;
California at San Diego, San Diego, CA 92093 United
College, Hanscom AFB, MA 01731 United States;
695, Greenbelt, MD 20771 United States;
Directorate, Air Force Research Laboratory, Hanscom
AFB, MA 01731 United States;
Observatory, Meudon, 92915 France;
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH11A-05
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 7534 Radio emissions,
6964 Radio wave propagation, 6969 Remote sensing
Bibliographic Code: 2004AGUFMSH11A..05R
Abstract
The low-frequency (kilometric) radio observations on Wind/WAVES provide
important spectral and directional information related to the
propagation of ICMEs through interplanetary space. However, up to now
there has been no white-light observations with which to compare these
low-frequency interplanetary radio observations, beyond the 30 Rs limit
of the LASCO field of view. The recently launched Air Force Coriolis
spacecraft that includes the Solar Mass Ejection Imager (SMEI), which is
the first all-sky camera designed to track ICMEs from the Sun to 1 AU,
provides a unique opportunity of simultaneously tracking CMEs, both in
white light and in radio, all the way from the corona to 1 AU. 3D
reconstruction techniques, utilizing multiple perspective views of the
ICME observed by SMEI, represent the propagation and evolution of these
density structures through the 3D heliosphere. There are two general
ways that the Wind/WAVES radio data can be directly related to the SMEI
heliospheric white-light observations. First, since the observed radio
frequency depends on the local plasma density in the radio source region
and since the interplanetary plasma density falls off with the inverse
of the heliocentric distance squared, the observed radio frequency
generated by the CME/shock decreases as the type II radio source
associated with the CME propagates farther from the Sun. Thus the
frequency characteristics of the type II radio emissions provide
information on the radial distance of the ICME. Secondly, the
low-frequency radio receivers on the Wind spacecraft have the unique
capability of providing information on the direction of arrival of the
radio emissions and of the size of the radio-emitting region. Both of
these results, obtained from analyses of the Wind/WAVES radio
observations, will be directly compared with the results from the
analyses of the SMEI white-light data for various ICME events.
Title: Heliospheric Photometric Images and 3D
Reconstruction from the Solar Mass Ejection Imager
(SMEI) Data
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, LaJolla, CA
Astrophysics and Space Sciences, University of
California at San Diego, LaJolla, CA 92093-0424 ;
and Space Sciences, University of California at San
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH11A-02
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 7594 Instruments and
techniques, 2102 Corotating streams, 2111 Ejecta,
driver gases, and magnetic clouds, 2164 Solar wind
plasma
Bibliographic Code: 2004AGUFMSH11A..02J
Abstract
The Solar Mass Ejection Imager (SMEI) experiment is fixed to the
Coriolis spacecraft and views the sky above Earth using
sunlight-rejecting baffles and CCD camera technology. SMEI was designed
to provide precise photometric white light images over most of the sky
on each 102-minute Earth orbit. The brightness sky maps of the inner
heliosphere indicate a rich variety of electron density structures that
are produced by the material that propagates through it and its
interaction with ambient structures. We present some of the
preliminary results of the analysis of these photometric SMEI
observations derived by modeling the white light observations such that
most of the contaminant signals: stars, the zodiacal cloud and
high-energy particle variations are removed. We will also show some of
the 3D reconstructions that allow this contaminant signal removal using
both interplanetary scintillation (IPS) and SMEI data.
Title: Three-dimensional structure of compound
interplanetary transients associated with 27-28 May
2003 coronal mass ejections
Authors: Tokumaru, M.; Kojima, M.; Fujiki, K.; Yamashita, M.;
Jackson, B. V.; Hick, P.
Affiliation: AA(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AB(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AC(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AD(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AE(CASS/UCSD, 9500 Gilman Dr., La Jolla, CA
AF(CASS/UCSD, 9500 Gilman Dr., La Jolla, CA
Publication: American Geophysical Union, Fall Meeting 2004,
abstract \#SH11A-01
Publication Date: 12/2004
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 2111 Ejecta, driver
gases, and magnetic clouds, 2139 Interplanetary
shocks, 2164 Solar wind plasma
Bibliographic Code: 2004AGUFMSH11A..01T
Abstract
We have investigated the global features of interplanetary (IP)
disturbances associated with 27-28 May coronal mass ejection (CME)
events using interplanetary scintillation (IPS) measurements of the
Solar-Terrestrial Environment Laboratory (STEL). Our IPS data taken
between 2003 May 28 22h UT and May 29 7h UT showed a set of complex
feature of IP disturbances, and most of them are regarded as IP
consequences of two full-halo CMEs which occurred in association with
the X1.3/2B flare on May 27 23:07 UT and the X3.3 flare on May 28 00:27
UT. Some components of the IP disturbances were discriminated from the
IPS data by making the model fitting analysis iteratively. One of the
components was an Earth-directed one, which appears to correspond to the
IP shock observed by ACE on May 29 18:30 UT. Other components were
obliquely propagating ones, which either preceded or followed the
Earth-directed one. The global features deduced here are generally in
agreement with heliospheric reconstructions made from Solar Mass
Ejection Imager (SMEI) measurements.
Title: Preliminary Three Dimensional Reconstruction of CMEs
Using Solar Mass Ejection Imager (SMEI) Data
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.;
Wang, X.
Affiliation: AA(CASS/UCSD), AB(CASS/UCSD), AC(CASS/UCSD),
AD(CASS/UCSD)
Publication: American Astronomical Society Meeting 205, \#43.05;
Bulletin of the American Astronomical Society, Vol.
36, p.1412
Publication Date: 12/2004
Origin: AAS
Bibliographic Code: 2004AAS...205.4305J
Abstract
White-light Thomson scattering observations from the Solar Mass Ejection
Imager (SMEI) have recorded the inner heliospheric response to the
October 28, 2003 CME. Here we detail the extent of this particular CME
event in SMEI observations, and we show how we are able to track the
event from its first measurement approximately 20o from the
solar disk until it fades away in the SMEI 180o field of
view. Several portions of this CME that can be tracked into the
interplanetary medium are associated with the initial CME response and
the underlying erupting prominence structure. We employ a 3D
reconstruction technique that provides perspective views from
outward-flowing solar wind as observed from Earth. This is accomplished
by iteratively fitting the parameters of a kinematic solar wind density
model to the SMEI white light observations and to Solar-Terrestrial
Environment Laboratory (STELab), interplanetary scintillation (IPS)
velocity data. This 3D modeling technique enables separating the true
heliospheric response in SMEI from background noise, and reconstructing
the 3D heliospheric structure as a function of time. These
reconstructions allow both separation of the 28 October CME from other
nearby heliospheric structure and a determination of its mass. The
preliminary SMEI white light calibration indicates a total mass of 6 X
1016g for the ejecta associated with the prominence eruption.
The total mass of this CME including possible associated nearby
structures may have been as much as 2 X 1017g of inner
heliospheric response spread over much of the Earthward-facing
hemisphere.
Title: Photometric Calibration for the Solar Mass Ejection
Imager (SMEI)
Authors: Buffington, A.; Smith, A. C.; Jackson, B. V.;
Hick, P. P.
Publication: American Astronomical Society Meeting 205, \#10.07;
Bulletin of the American Astronomical Society, Vol.
36, p.1350
Publication Date: 12/2004
Origin: AAS
Bibliographic Code: 2004AAS...205.1007B
Abstract
The Solar Mass Ejection Imager (SMEI) was designed to record a
photometric white-light response of the interplanetary medium from Earth
over most of the sky in near real time, using Thomson scattered
sunlight. In its first two years the instrument has observed several
hundred Coronal Mass Ejections. Quantitative interpretations of these
data requires that the Analog Data Units (ADUs) of the instrument's CCD
responses be converted to an effective stellar brightness. The present
work provides a preliminary report on establishing this relationship.
An appropriate unit here is an "S10", the equivalent brightness of a
10th magnitude star spread over one square degree. The relationship
between ADUs and S10s is established by using the SMEI response to
bright stars having known visual magnitude and spectral type. These
latter are converted to a "SMEI magnitude" by integrating the various
star's spectra over the nominal SMEI bandpass, which extends between 0.4
and 1.1 microns and peaks at 0.7 microns, to obtain a spectral scaling
factor which is set to unity for G-type stars and relates visual
magnitudes to SMEI magnitudes. The final overall conversion factor is
then determined from the ADU measurements of the individual stars.
This work was supported in part by NSF contract ATM0331513 and NASA
grant NAG 5-134543.
Title: Near Real-Time Photometric Data Processing for the
Solar Mass Ejection Imager (SMEI)
Authors: Hick, P. P.; Buffington, A.; Jackson, B. V.
Affiliation: AA(UCSD/CASS), AB(UCSD/CASS), AC(UCSD/CASS)
Publication: American Astronomical Society Meeting 205, \#10.06;
Bulletin of the American Astronomical Society, Vol.
36, p.1350
Publication Date: 12/2004
Origin: AAS
Bibliographic Code: 2004AAS...205.1006H
Abstract
The Solar Mass Ejection Imager (SMEI) records a photometric white-light
response of the interplanetary medium from Earth over most of the sky in
near real time. In the first two years of operation the instrument has
recorded the inner heliospheric response to several hundred CMEs,
including the May 28, 2003 and the October 28, 2003 halo CMEs. In this
preliminary work we present the techniques required to process the SMEI
data from the time the raw CCD images become available to their final
assembly in photometrically accurate maps of the sky brightness relative
to a long-term time base.
Processing of the SMEI data includes integration of new data into the
SMEI data base; a conditioning program that removes from the raw CCD
images an electronic offset ("pedestal") and a temperature-dependent
dark current pattern; an "indexing" program that places these CCD images
onto a high-resolution sidereal grid using known spacecraft pointing
information. At this "indexing" stage further conditioning removes the
bulk of the the effects of high-energy-particle hits ("cosmic rays"),
space debris inside the field of view, and pixels with a sudden state
change ("flipper pixels").
Once the high-resolution grid is produced, it is reformatted to a
lower-resolution set of sidereal maps of sky brightness. From these
sidereal maps we remove bright stars, background stars, and a zodiacal
cloud model (their brightnesses are retained as additional data
products). The final maps can be represented in any convenient sky
coordinate system. Common formats are Sun-centered Hammer-Aitoff or
"fisheye" maps. Time series at selected locations on these maps are
extracted and processed further to remove aurorae, variable stars and
other unwanted signals. These time series (with a long-term base
removed) are used in 3D tomographic reconstructions.
The data processing is distributed over multiple PCs running Linux, and,
runs as much as possible automatically using recurring batch jobs
('cronjobs'). The batch scrips are controlled by Python scripts. The
core data processing routines are written in several computer languages:
Fortran, C++ and IDL.
Title: Interactive Visualization of Solar Mass Ejection
Imager (SMEI) Volumetric Data
Authors: Wang, X.; Hick, P. P.; Jackson, B. V.
Affiliation: AA(UCSD), AB(UCSD), AC(UCSD)
Publication: American Astronomical Society Meeting 205, \#10.05;
Bulletin of the American Astronomical Society, Vol.
36, p.1350
Publication Date: 12/2004
Origin: AAS
Bibliographic Code: 2004AAS...205.1005W
Abstract
We present a volume rendering system developed for the real time
visualization and manipulation of 3D heliospheric volumetric solar wind
density and velocity data obtained from the Solar Mass Ejection Imager
(SMEI) and interplanetary scintillation (IPS) velocities over the same
time period. Our system exploits the capabilities of the VolumePro 1000
board from TeraRecon, Inc., a low-cost 64-bit PCI board capable of
rendering up to a 512-cubed array of volume data in real time at up to
30 frames per second on a standard PC. Many volume-rendering operations
have been implemented with this system such as stereo/perspective views,
animations of time-sequences, and determination of CME volumes and
masses. In these visualizations we highlight two time periods where halo
CMEs were observed by SMEI to engulf Earth, on May 30, 2003 and on
October 29, 2003. We demonstrate how this system is used to measure the
distribution of structure and provide 3D mass for individual CME
features, including the ejecta associated with the large prominence
viewed moving to the south of Earth following the late October CME.
Title: The Solar Mass-Ejection Imager (SMEI) Mission
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.;
Altrock, R. C.; Figueroa, S.; Holladay, P. E.;
Johnston, J. C.; Kahler, S. W.; Mozer, J. B.;
Price, S.; Radick, R. R.; Sagalyn, R.; Sinclair, D.;
Simnett, G. M.; Eyles, C. J.; Cooke, M. P.;
Tappin, S. J.; Kuchar, T.; Mizuno, D.; Webb, D. F.;
Anderson, P. A.; Keil, S. L.; Gold, R. E.;
Waltham, N. R.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego), AB(Center
for Astrophysics and Space Sciences, University of
California at San Diego), AC(Center for Astrophysics
and Space Sciences, University of California at San
Diego), AD(Air Force Research Laboratory/Space
Vehicles Directorate (AFRL/VS)), AE(Air Force
Research Laboratory/Space Vehicles Directorate
(AFRL/VS)), AF(Air Force Research Laboratory/Space
Vehicles Directorate (AFRL/VS)), AG(Air Force
Research Laboratory/Space Vehicles Directorate
(AFRL/VS)), AH(Air Force Research Laboratory/Space
Vehicles Directorate (AFRL/VS)), AI(Air Force
Research Laboratory/Space Vehicles Directorate
(AFRL/VS)), AJ(Air Force Research Laboratory/Space
Vehicles Directorate (AFRL/VS)), AK(Air Force
Research Laboratory/Space Vehicles Directorate
(AFRL/VS)), AL(Air Force Research Laboratory/Space
Vehicles Directorate (AFRL/VS)), AM(Air Force
Research Laboratory/Space Vehicles Directorate
(AFRL/VS)), AN(School of Physics and Space Research,
University of Birmingham), AO(School of Physics and
Space Research, University of Birmingham), AP(School
of Physics and Space Research, University of
Birmingham), AQ(School of Physics and Space
Research, University of Birmingham), AR(ISR, Boston
College), AS(ISR, Boston College), AT(ISR, Boston
College), AU(Boston University), AV(National Solar
Observatory), AW(Applied Physics Laboratory, Johns
Hopkins University), AX(Space Science Department,
Rutherford-Appleton Laboratory)
Publication: Solar Physics, Volume 225, Issue 1, pp.177-207
Publication Date: 11/2004
Origin: SPRINGER
DOI: 10.1007/s11207-004-2766-3
Bibliographic Code: 2004SoPh..225..177J
Abstract
We have launched into near-Earth orbit a solar mass-ejection imager
(SMEI) that is capable of measuring sunlight Thomson-scattered from
heliospheric electrons from elongations to as close as
18o to greater than 90o from the Sun. SMEI
is designed to observe time-varying heliospheric brightness of objects
such as coronal mass ejections, co-rotating structures and shock waves.
The instrument evolved from the heliospheric imaging capability
demonstrated by the zodiacal light photometers of the Helios spacecraft.
A near-Earth imager can provide up to three days warning of the arrival
of a mass ejection from the Sun. In combination with other imaging
instruments in deep space, or alone by making some simple assumptions
about the outward flow of the solar wind, SMEI can provide a
three-dimensional reconstruction of the surrounding heliospheric density
structures.
Title: Demonstration of the TIRGO compact 800- to 900-GHz
heterodyne receiver on UKIRT
Authors: Ellison, Brian N.; Little, Leslie T.;
Davies, Steven R.; White, Glenn J.; Price, Mark C.;
Matheson, David N.; Jackson, Brian D.;
Natale, Vincenzo
Affiliation: AA(Rutherford Appleton Lab. (United Kingdom)),
AB(Univ. of Kent/Canterbury (United Kingdom)),
AC(Univ. of Bath (United Kingdom)), AD(Univ. of
Kent/Canterbury (United Kingdom)), AE(Univ. of
Kent/Canterbury (United Kingdom)), AF(Rutherford
Appleton Lab. (United Kingdom)), AG(Space Research
Organization of the Netherlands (Netherlands)),
AH(Consiglio Nazionale delle Ricerche (Italy))
Publication: Millimeter and Submillimeter Detectors for Astronomy
II. Edited by Jonas Zmuidzinas, Wayne S. Holland
and Stafford Withington Proceedings of the SPIE,
Volume 5498, pp. 705-712 (2004).
Publication Date: 10/2004
Origin: SPIE
DOI: 10.1117/12.553234
Bibliographic Code: 2004SPIE.5498..705E
Abstract
A compact sub-millimetre wavelength Nb superconducting tunnel junction
receiver (TIRGO) has been installed on the UKIRT facility, Hawaii. The
receiver, used in combination with an acousto-optic spectrometer,
exhibited excellent noise performance, achieving a best noise equivalent
temperature of 280K (DSB) at 808GHz. Despite unfavourable observing
conditions, spectral observations of a variety of astronomical sources
were made that effectively verified the sensitivity and usefulness of
the instrument for astronomical research. The design, construction and
performance of the receiver system are described and some of the
astronomical data acquired during the observation period briefly
presented.
Title: Development of the HIFI band 3 and 4 mixer units
Authors: de Lange, Gert; Jackson, Brian D.; Eggens, M.;
Golstein, H.; Jochemsen, Marinus; Laauwen, W. M.;
de Jong, L.; Kikken, S.; Pieters, C.; Smit, H.;
Van Nguyen, D.; Kroug, Matthias; Zijlstra, Tony;
Klapwijk, Teun M.
Affiliation: AA(SRON National Institute for Space Research
(Netherlands)), AB(SRON National Institute for Space
Research (Netherlands)), AC(SRON National Institute
for Space Research (Netherlands)), AD(SRON National
Institute for Space Research (Netherlands)), AE(SRON
National Institute for Space Research
(Netherlands)), AF(SRON National Institute for Space
Research (Netherlands)), AG(SRON National Institute
for Space Research (Netherlands)), AH(SRON National
Institute for Space Research (Netherlands)), AI(SRON
National Institute for Space Research
(Netherlands)), AJ(SRON National Institute for Space
Research (Netherlands)), AK(SRON National Institute
for Space Research (Netherlands)), AL(Delft Univ. of
Technology (Netherlands)), AM(Delft Univ. of
Technology (Netherlands)), AN(Delft Univ. of
Technology (Netherlands))
Publication: Millimeter and Submillimeter Detectors for Astronomy
II. Edited by Jonas Zmuidzinas, Wayne S. Holland
and Stafford Withington Proceedings of the SPIE,
Volume 5498, pp. 268-277 (2004).
Publication Date: 10/2004
Origin: SPIE
DOI: 10.1117/12.552585
Bibliographic Code: 2004SPIE.5498..268D
Abstract
We describe the current status of the HIFI mixer units for Band 3 and
Band 4. The mixer units cover the 800-960 GHz and 960-1120 GHz frequency
range and have a 4-8 GHz IF frequency band. The major requirements and
the design strategy are described. Functional tests of the magnet, the
de-flux heater, IF-circuit, and the corrugated horn were performed.
Details of the design of the mixer units and the performance status are
presented. The DSB receiver noise performance ranges from 210 K at 850
GHz to 430 K at 1075 GHz.
Title: Exploratory Submm Space Radio-Interferometric
Telescope (ESPRIT)
Authors: de Graauw, Thijs W.; Cernicharo, J.; Wild, Wolfgang;
Bos, A.; Bregman, Jaap D.; D'Arcio, Luigi L. A.;
den Herder, Jan-Willem; Gunst, A. W.; Helmich, F.;
Jackson, Brian D.; Maat, P.; Martin-Pintado, Jes{\'{u}}s;
Noordam, Jan E.; Quirrenbach, Andreas;
Roelfsema, Peter R.; Venema, Lars B.;
Wesselius, Paul; Yagoubov, Pavel A.
Affiliation: AA(Space Research Organization Netherlands
(Netherlands) and Univ. Leiden (Netherlands)),
AB(Consejo Superior de Investigaciones Cientificas
(Spain)), AC(Space Research Organization Netherlands
(Netherlands) and Kapteyn Astronomical Institute
(Netherlands)), AD(ASTRON (Netherlands)), AE(ASTRON
(Netherlands)), AF(Leiden Observatory
(Netherlands)), AG(Space Research Organization
Netherlands (Netherlands)), AH(ASTRON
(Netherlands)), AI(Space Research Organization
Netherlands (Netherlands)), AJ(Space Research
Organization Netherlands (Netherlands)), AK(ASTRON
(Netherlands)), AL(Consejo Superior de
Investigaciones Cientificas (Spain)), AM(ASTRON
(Netherlands)), AN(Leiden Observatory
(Netherlands)), AO(Space Research Organization
Netherlands (Netherlands) and Kapteyn Astronomical
Institute (Netherlands)), AP(ASTRON (Netherlands)),
AQ(Space Research Organization Netherlands
(Netherlands) and Kapteyn Astronomical Institute
(Netherlands)), AR(Space Research Organization
Netherlands (Netherlands))
Publication: Optical, Infrared, and Millimeter Space Telescopes.
Edited by Mather, John C. Proceedings of the
SPIE, Volume 5487, pp. 1522-1526 (2004).
Publication Date: 10/2004
Origin: SPIE
DOI: 10.1117/12.552610
Bibliographic Code: 2004SPIE.5487.1522D
Abstract
The far-infrared (FIR) wavelength regime has become of prime importance
for astrophysics. Observations of ionic, atomic and molecular lines,
many of them present in the FIR, provide important and unique
information on the star and planet formation process occurring in
interstellar clouds, and on the lifecycle of gas and dust in general. As
these regions are heavily obscured by dust, FIR observations are the
only means of getting insight in the physical and chemical conditions
and their evolution. These investigations require, besides high
spectral, also high angular resolution in order to match the small
angular sizes of star forming cores and circum-stellar disks. We present
here a mission concept, ESPRIT, which will provide both, in a wavelength
regime not accessible from ground by ALMA (Atacama Large Millimeter
Array), nor with JWST (James Webb Space Telescope).
Title: Collisions and expansion of an ultracold dilute
Fermi gas
Authors: Jackson, B.; Pedri, P.; Stringari, S.
Affiliation: AA(Dipartimento di Fisica, Università di Trento and
BEC-INFM I-38050 Povo (TN) Italy ), AB(Dipartimento
di Fisica, Università di Trento and BEC-INFM I-38050
Povo (TN) Italy; Institut für Theoretische Physik,
Universität Hannover D-30167 Hannover, Germany),
AC(Dipartimento di Fisica, Università di Trento and
BEC-INFM I-38050 Povo (TN) Italy )
Publication: Europhysics Letters, Volume 67, Issue 4, pp. 524-530
(2004).
Publication Date: 08/2004
Origin: IOP
DOI: 10.1209/epl/i2004-10086-8
Bibliographic Code: 2004EL.....67..524J
Abstract
We discuss the effects of collisions on the expansion of a degenerate
normal Fermi gas, following the sudden removal of the confining trap.
Using a Boltzmann equation approach, we calculate the time dependence of
the aspect ratio and the entropy increase of the expanding atomic cloud
taking into account the collisional effects due to the deformation of
the distribution function in momentum space. We find that in dilute
gases the aspect ratio does not deviate significantly from the
predictions of ballistic expansion. Conversely, if the trap is
sufficiently elongated, the thermal broadening of the density
distribution due to the entropy increase can be sizeable, revealing that
even at zero temperature collisions are effective in a Fermi gas.
Title: The Solar Mass Ejection Imager (SMEI) and Its
Potential as a Precision Time-Series Photometer
Authors: Buffington, A.; Jackson, B. V.; Hick, P. P.;
Penny, A.
Affiliation: AA(Center for Astrophysics and Space Sciences, Univ.
of Calif. San Diego, La Jolla, CA), AB(Center for
Astrophysics and Space Sciences, Univ. of Calif. San
Diego, La Jolla, CA), AC(Center for Astrophysics and
Space Sciences, Univ. of Calif. San Diego, La Jolla,
CA), AD(Space Science Department,
Rutherford-Appleton Laboratory, Chilton, UK.)
Publication: American Astronomical Society Meeting 204, \#69.10;
Bulletin of the American Astronomical Society, Vol.
36, p.795
Publication Date: 05/2004
Origin: AAS
Bibliographic Code: 2004AAS...204.6910B
Abstract
The Solar Mass Ejection Imager (SMEI) was launched in January 2003 into
Earth orbit. SMEI is designed to observe heliospheric structures
illuminated by Thomson-scattered sunlight. The design specification for
SMEI is 0.1% in differential photometry for bright unresolved objects,
to enable star removal from the heliospheric maps. Such a near-Earth
imager will also provide photometric time-series measurements of these
stars as a by-product of this removal process. For each 101-minute
orbit, SMEI will deliver near complete sky maps having an expected (1
sigma) photometric resolution of about the equivalent of an 11th
magnitude star in a square degree. We will report on progress in
establishing the photometric calibrations for the SMEI cameras, and
discuss SMEI's potential for delivering photometric time-series
measurements, which data can then be applied to the study of variable
stars, eclipsing stellar systems, and to search for extrasolar planets
by the occultation method.
Title: Coronal Mass Ejection Masses From CMEs Identified in
Interplanetary Scintillation (IPS) Tomography and
LASCO Coronagraph Images
Authors: Rappoport, S. A.; Jackson, B. V.; Hick, P. P.;
Buffington, A.; Vourlidas, A.
Affiliation: AA(CASS/ UCSD), AB(CASS/UCSD), AC(CASS/UCSD),
AD(CASS/UCSD), AE(NRL)
Publication: American Astronomical Society Meeting 204, \#38.02;
Bulletin of the American Astronomical Society, Vol.
36, p.712
Publication Date: 05/2004
Origin: AAS
Bibliographic Code: 2004AAS...204.3802R
Abstract
To optimize the information from individual radio source observations of
the sky covering large elongations, we have developed a
Computer-Assisted Tomography (CAT) program. We fit STELab (Nagoya
University, Japan) interplanetary scintillation (IPS) observations to a
time-dependent, three-dimensional heliospheric model. These observations
allow us to create "sky maps" covering 10 to 80 degrees in elongation,
in which we can track CMEs observed earlier in LASCO coronagraph images.
These events have approximately the same shapes and extents as observed
closer to the Sun. Here we map several CMEs in 3-dimensions as they move
outward to 1 AU. Masses for each of the events are determined from the
reconstruction analysis and are compared with plane of the sky masses
obtained from calibrated LASCO coronagraph images.
Title: The Solar Mass Ejection Imager (SMEI) Mission
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.;
Kuchar, T.; Mizuno, D.; Webb, D. F.
Affiliation: AA(CASS/University of California at San Diego),
AB(CASS/University of California at San Diego),
AC(CASS/University of California at San Diego),
AD(ISR, Boston College), AE(ISR, Boston College),
AF(ISR, Boston College)
Publication: American Astronomical Society Meeting 204, \#18.09;
Bulletin of the American Astronomical Society, Vol.
36, p.684
Publication Date: 05/2004
Origin: AAS
Bibliographic Code: 2004AAS...204.1809J
Abstract
The Solar Mass Ejection Imager (SMEI) was launched in January 2003 into
Earth orbit. It observes sunlight that has Thomson-scattered from
heliospheric structures of time-varying density. SMEI is designed to
observe heliospheric structures such as coronal mass ejections (CMEs),
corotating structures and shock waves to elongations greater than 90
degrees from the Sun. Such a near-Earth imager can provide up to three
days warning of the arrival of a CME from the Sun. In combination with
other imaging instruments in deep space, or alone by making some simple
assumptions about the outward flow of the solar wind, SMEI can provide
3D reconstructions of the heliospheric structures that it observes. We
show images of several CMEs observed with this instrument and
low-resolution reconstruction analyses using the SMEI data for each
event. The 3D reconstructions and heights for these events are compared
with elongation-time plots of the same CMEs to estimate true speeds and
line-of-sight locations for each CME.
Title: Theoretical study of methane dissociative
chemisorption on metal surfaces at finite
temperatures
Authors: Quattrucci, Joseph; Jackson, Bret
Affiliation: University of Massachusetts
Publication: American Physical Society, March Meeting 2004, March
22-26, 2004, Palais des Congres de Montreal,
Montreal, Quebec, Canada, MEETING ID: MAR04,
abstract \#H35.004
Publication Date: 03/2004
Origin: APS
Bibliographic Code: 2004APS..MARH35004Q
Abstract
We present a four dimensional quantum mechanical model for studying the
dissociative chemisorption of methane on metal surfaces at finite
temperatures. We make a flat surface approximation and treat methane as
a quasidiatomic molecule, R-H. The local distortion of the lattice is
described by a single degree of freedom, Q. We take into account the
changes in the potential energy surface (PES), namely the barrier height
and width, due to lattice motion, by expanding the parameters describing
our PES in terms of Q. Our model PES is fit to the results of extensive
total energy calculations based on Density Functional Theory. Various
lattice distortions are considered in these calculations. We present
results for Ni(111) surface.
Title: Resonance states in the trapping of H on the
graphite (0001) surface
Authors: Lemoine, Didier; Jackson, Bret; Sha, Xianwei
Affiliation: AA(Laboratoire Collisions, Agrégats, Réactivité, UMR
CNRS 5589, Université Paul Sabatier, Bâtiment
3R1B4,118 route de Narbonne, 31062 Toulouse cedex,
France) AB(Department of Chemistry, University of
Massachusetts, Amherst, MA 01003, USA) AC(Department
of Chemistry, University of Massachusetts, Amherst,
MA 01003, USA)
Publication: American Physical Society, March Meeting 2004, March
22-26, 2004, Palais des Congres de Montreal,
Montreal, Quebec, Canada, MEETING ID: MAR04,
abstract \#B35.011
Publication Date: 03/2004
Origin: APS
Bibliographic Code: 2004APS..MARB35011L
Abstract
A fully quantum mechanical model is used to investigate the trapping of
H and D atoms on a graphite (0001) surface. We are specifically
interested in the chemisorption of H on graphite, which requires a
significant puckering of the bonding carbon. Our model allows for the
full three dimensional motion of the H atom and the puckering of the
bonding carbon, but assumes that the surface is flat otherwise.
Initially, the incident H atom traps into a quasi-bound resonance state,
and we examine these resonance states and their widths (lifetimes). A
potential energy surface based on density functional total energy
calculations is used.
Title: The chemisorption of H atoms on the graphite (0001)
surface: trying to understand the sticking
probability
Authors: Sha, Xianwei; Jackson, Bret; Lemoine, Didier
Affiliation: AA(University of Massachusetts, Amherst, MA)
AB(University of Massachusetts, Amherst, MA)
AC(Universite Paul Sabatier, Toulouse, France)
Publication: American Physical Society, March Meeting 2004, March
22-26, 2004, Palais des Congres de Montreal,
Montreal, Quebec, Canada, MEETING ID: MAR04,
abstract \#B35.010
Publication Date: 03/2004
Origin: APS
Bibliographic Code: 2004APS..MARB35010S
Abstract
It has been suggested theoretically and proven experimentally that H
atoms can chemisorb onto graphite (0001) surfaces. The H atom bonds
directly to a carbon atom which puckers out of the surface by several
tenths of an Angstrom. This lattice distortion generates a barrier to
chemisorption of about 0.2 eV. Experiments involving thermal H and D
atom sources have confirmed the existence of this barrier, but suggest
that the sticking probabilities are large - 20% or more. This seems
large, given that the carbon lattice must rapidly distort in order to
chemisorb the H. We present the results of extensive electronic
structure calculations (based on Density Functional Theory) which
explore the H-graphite interaction as a function of the lattice
puckering. The potential energy surfaces generated will be used to
compute H-graphite and D-graphite sticking probabilities on graphite.
Title: Adsorption and abstraction of H atoms on graphite
zigzag edges
Authors: Sha, Xianwei; Jackson, Bret
Affiliation: Department of Chemistry, University of
Massachusetts, Amherst, MA01003, USA
Publication: American Physical Society, March Meeting 2004, March
22-26, 2004, Palais des Congres de Montreal,
Montreal, Quebec, Canada, MEETING ID: MAR04,
abstract \#B35.009
Publication Date: 03/2004
Origin: APS
Bibliographic Code: 2004APS..MARB35009S
Abstract
Adsorption and abstraction reactions of H atoms on a (10-10) graphite
zigzag edge have been investigated theoretically. First-principles total
energy calculations based on density functional theory have been
performed to study the electronic, structural, vibrational and energetic
properties of H atoms chemisorbed on a graphite edge. Two different
chemisorption configurations have been found: one H atom can be
chemisorbed directly on an edge Caron edge Carbon site. Under exposure
to a flux of incident H atoms, one chemisorption configuration can be
transformed into the other by the addition or subtraction of one
chemisorbed H atom. Molecular hydrogen can also dissociatively adsorb on
the graphite edge, forming the two H co-chemisorbed configuration
directly. A detailed comparison has been made with theoretical and
experimental data of H on the graphite (0001) surface, as well as
available experimental results for hydrogen storage in graphite
nanostructures.
Title: Heliospheric tomography: an algorithm for the
reconstruction of the 3D solar wind from remote
sensing observations
Authors: Hick, P. P.; Jackson, Bernard V.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA))
Publication: Telescopes and Instrumentation for Solar
Astrophysics. Edited by Fineschi, Silvano; Gummin,
Mark A. Proceedings of the SPIE, Volume 5171, pp.
287-297 (2004).
Publication Date: 02/2004
Origin: SPIE
DOI: 10.1117/12.513122
Bibliographic Code: 2004SPIE.5171..287H
Abstract
Over the past years we have developed a tomographic technique for using
heliospheric remote sensing observations (i.e. interplanetary
scintillation and Thomson scattering data) for the reconstruction of the
three-dimensional solar wind density and velocity in the inner
heliosphere. We describe the basic algorithm on which our technique is
based. To highlight the details of the reconstruction algorithm we
specifically emphasize the implementation of corotating tomography using
IPS g-level and IPS velocity observations as proxies for the solar wind
density and velocity, respectively. We provide some insight into the
modifications required to expand the technique into a fully
time-dependent tomography, and to use Thomson scattering brightness
(instead of g-level) as a proxy for the solar wind density.
Title: Visualization of remotely sensed heliospheric
plasmas for space weather applications
Authors: Wang, Xin; Hick, P. P.; Jackson, Bernard V.;
Bailey, Mike
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA)), AD(Univ. of
California/San Diego (USA))
Publication: Telescopes and Instrumentation for Solar
Astrophysics. Edited by Fineschi, Silvano; Gummin,
Mark A. Proceedings of the SPIE, Volume 5171, pp.
280-286 (2004).
Publication Date: 02/2004
Origin: SPIE
DOI: 10.1117/12.513117
Bibliographic Code: 2004SPIE.5171..280W
Abstract
We demonstrate a software application designed for the display and
interactive manipulation of 3D heliospheric volume data, such as solar
wind density, velocity and magnetic field. The Volume Explorer software
exploits the capabilities of the Volume Pro 1000 (from TeraRecon, Inc.),
a low-cost 64-bit PCI board capable of rendering a 512-cubed array of
volume data in real time at up to 30 frames per second on a standard PC.
The application allows stereo and perspective views, and animations of
time-sequences. We show examples of three-dimensional heliospheric
volume data derived from tomographic reconstructions based on
heliospheric remote sensing observations of the heliospheric density and
velocity structure. Currently these reconstructions are based on
archival IPS and Thomson scattering data. In the near future we expect
to add reconstructions based on the all-sky observations from the
recently launched Solar Mass Ejection Imager.
Title: Comparative analyses of the CSSS magnetic field
calculation in the Univ. of California/San Diego
tomographic solar wind model with in situ spacecraft
observations
Authors: Dunn, Tamsen; Hick, P. P.; Jackson, Bernard V.;
Buffington, Andrew; Zhao, Xue Pu
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA)), AD(Univ. of
California/San Diego (USA)), AE(Stanford Univ.
(USA))
Publication: Telescopes and Instrumentation for Solar
Astrophysics. Edited by Fineschi, Silvano; Gummin,
Mark A. Proceedings of the SPIE, Volume 5171, pp.
6-13 (2004).
Publication Date: 02/2004
Origin: SPIE
DOI: 10.1117/12.513759
Bibliographic Code: 2004SPIE.5171....6D
Abstract
Our tomographic techniques developed over the last few years are based
on kinematic models of the solar wind. This allows us to determine the
large-scale three-dimensional extents of solar wind structures using
interplanetary scintillation (IPS) observations and Thomson scattering
brightness data in order to forecast their arrival at Earth in real
time. We are specifically interested in a technique that can be combined
with observations presently available from IPS velocity data and with
observations which will become available from the Solar Mass Ejection
Imager. In this paper, we introduce magnetic field projections from
solar surface magnetogram data using the Stanford Current-Sheet Source
Surface model at the source surface of our model and extrapolate the
magnetic field out to and beyond Earth. The results are compared with in
situ data. Real time projections of these data are available on our web
site at: http://cassfos02.ucsd.edu/solar/forecast/index_v_n.html and
http://cassfos02.ucsd.edu/solar/forecast/index_br_bt.html
Title: SMEI: design and development of an Earth-orbiting
all-sky coronagraph
Authors: Jackson, Bernard V.; Hick, P. P.; Buffington, Andrew;
Gold, Robert E.; Simnett, George M.;
Eyles, Christopher J.; Cooke, Mark P.;
Waltham, Nicholas R.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA)), AD(Johns Hopkins Univ.
(USA)), AE(Univ. of Birmingham (United Kingdom)),
AF(Univ. of Birmingham (United Kingdom)), AG(Univ.
of Birmingham (United Kingdom)), AH(Rutherford
Appleton Lab. (United Kingdom))
Publication: Telescopes and Instrumentation for Solar
Astrophysics. Edited by Fineschi, Silvano; Gummin,
Mark A. Proceedings of the SPIE, Volume 5171, pp.
1-5 (2004).
Publication Date: 02/2004
Origin: SPIE
DOI: 10.1117/12.513469
Bibliographic Code: 2004SPIE.5171....1J
Abstract
The Air Force/NASA Solar Mass Ejection Imager (SMEI) launched January 6,
2003 is now recording whole sky data on each 100-minute orbit. Precise
photometric sky maps of the heliosphere around Earth are expected from
these data. The SMEI instrument extends the heritage of the HELIOS
spacecraft photometer systems that have recorded CMEs and other
heliospheric structures from close to the Sun into the anti-solar
hemisphere. SMEI rotates once per orbit and views the sky away from
Earth using CCD camera technology. To optimize the information derived
from this and similar instruments, a tomographic technique has been
developed for analyzing remote sensing observations of the heliosphere
as observed in Thomson scattering. The technique provides 3-dimensional
reconstructions of heliospheric density. The tomography program has been
refined to analyze time-dependent phenomena such as evolving corotating
heliospheric structures and more discrete events such as coronal mass
ejections (CMEs), and this improved analysis is being applied to the
SMEI data.
Title: Tracking a major interplanetary disturbance with
SMEI
Authors: Tappin, S. J.; Buffington, A.; Cooke, M. P.;
Eyles, C. J.; Hick, P. P.; Holladay, P. E.;
Jackson, B. V.; Johnston, J. C.; Kuchar, T.;
Mizuno, D.; Mozer, J. B.; Price, S.; Radick, R. R.;
Simnett, G. M.; Sinclair, D.; Waltham, N. R.;
Webb, D. F.
Publication: Geophysical Research Letters, Volume 31, Issue 2,
CiteID L02802
Publication Date: 01/2004
Origin: AGU
AGU Keywords: Interplanetary Physics: Instruments and techniques,
Magnetospheric Physics: Storms and substorms, Solar
Physics, Astrophysics, and Astronomy: Coronal mass
ejections
DOI: 10.1029/2003GL018766
Bibliographic Code: 2004GeoRL..3102802T
Abstract
We present the first clear observations of an Earth-directed
interplanetary disturbance tracked by the Solar Mass Ejection Imager
(SMEI). We find that this event can be related to two halo CMEs seen at
the Sun about 2 days earlier, and which merged in transit to 1 AU. The
disturbance was seen about 16 hours before it reached Earth,and caused a
severe geomagnetic storm at the time which would have been predicted had
SMEI been operating as a real-time monitor. It is concluded that SMEI is
capable of giving many hours advance warning of the possible arrival of
interplanetary disturbances.
Title: Recent Comparative Analyses of the CSSS UCSD
Tomographic Solar Wind Model with in situ Spacecraft
Observations
Authors: Dunn, T.; Hick, P.; Jackson, B. V.; Buffington, A.
Affiliation: AA(CASS/UCSD, CASS 0424 9500 Gilman Drive, La
Jolla, CA 92093-0424 United States;
Gilman Drive, La Jolla, CA 92093-0424 United
9500 Gilman Drive, La Jolla, CA 92093-0424 United
0424 9500 Gilman Drive, La Jolla, CA 92093-0424
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH42B-0526
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 2722 Forecasting, 7513 Coronal mass ejections, 7524
Magnetic fields, 7594 Instruments and techniques
Bibliographic Code: 2003AGUFMSH42B0526D
Abstract
Our tomographic techniques developed over the last few years are based
on kinematic models of the solar wind. This allows us to determine the
large-scale three-dimensional extents of solar wind structures using
interplanetary scintillation (IPS) observations and Thomson scattering
brightness data in order to forecast their arrival at Earth in real
time. We are specifically interested in a technique that can be
combined with observations presently available from IPS velocity data
and with observations which are now becoming available from the Solar
Mass Ejection Imager. We use solar surface magnetogram data, and a
source surface provided by the Stanford Current-Sheet Source Surface
model, to provide input to the UCSD tomography program. The UCSD
tomography program extrapolates the magnetic field out to and beyond
Earth. The latest results are compared with in situ data.
Title: Stellar Variability Studies with SMEI
Authors: Penny, A. J.; Jackson, B. V.; Buffington, A.;
Hick, P. P.; Kahler, S. W.; Price, S.;
Johnston, J. C.; Holladay, P.; Sinclair, D.;
Radick, R. R.; Mozer, J. C.; Anderson, P.;
Simnett, G. M.; Eyles, C. J.; Cooke, M. P.;
Tappin, J.; Waltham, N. R.; Kuchnar, T.; Mizuno, D.;
Webb, D. F.
Affiliation: AA(Rutherford Appleton Laboratory, Chilton, Didcot,
AB(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
92093 United States; ), AC(Center for Astrophysics
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093 United States; ),
AD(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
92093 United States; ), AE(Air Force Research
Laboratory/Space Vehicles Directorate (AFRL/VS),
Hanscom AFB, Hanscom, MA 01731 United States; ),
AF(Air Force Research Laboratory/Space Vehicles
Directorate (AFRL/VS), Hanscom AFB, Hanscom, MA
01731 United States; ), AG(Air Force Research
Laboratory/Space Vehicles Directorate (AFRL/VS),
Hanscom AFB, Hanscom, MA 01731 United States; ),
AH(Air Force Research Laboratory/Space Vehicles
Directorate (AFRL/VS), Hanscom AFB, Hanscom, MA
01731 United States; ), AI(Air Force Research
Laboratory/Space Vehicles Directorate (AFRL/VS),
Hanscom AFB, Hanscom, MA 01731 United States; ),
AJ(Air Force Research Laboratory/Space Vehicles
Directorate (AFRL/VS), Hanscom AFB, Hanscom, MA
01731 United States; ), AK(Air Force Research
Laboratory/Space Vehicles Directorate (AFRL/VS),
Hanscom AFB, Hanscom, MA 01731 United States; ),
AL(Boston University, One Sherborn Street, Boston,
MA 02215 United States; ), AM(University of
Birmingham, University Road, Birmingham, Bir B15
2TT United Kingdom; ), AN(University of Birmingham,
University Road, Birmingham, Bir B15 2TT United
Kingdom; ), AO(University of Birmingham, University
Road, Birmingham, Bir B15 2TT United Kingdom; ),
AP(University of Birmingham, University Road,
Birmingham, Bir B15 2TT United Kingdom; ),
AQ(Rutherford Appleton Laboratory, Chilton, Didcot,
Oxf OX1 1TY United Kingdom; ), AR(Boston College,
Newton Centre, Boston, MA 02459 United States; ),
AS(Boston College, Newton Centre, Boston, MA 02459
United States; ), AT(Boston College, Newton Centre,
Boston, MA 02459 United States; )
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41C-08
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 7539 Stellar astronomy
Bibliographic Code: 2003AGUFMSH41C..08P
Abstract
The Solar Mass Ejection Imager (SMEI) instrument images most of the sky
every 105 minutes. From this unique dataset, the brightnesses of stars
down to and below the eight magnitude can be measured to investigate
their variability. This paper presents the methods developed to extract
the stellar brightnesses, and the accuracies obtained as a function of
brightness and crowding. Example lightcurves are given.
Title: IPS/SMEI potential joint observations
Authors: Tokumaru, M.; Kojima, M.; Fujiki, K.; Jackson, B. V.;
Hick, P.
Affiliation: AA(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AB(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AC(STE Lab., Nagoya Univ., 3-13 Honohara, Toyokawa,
AD(CASS/UCSD, 9500 Gilman Dr., La Jolla,, San
Diego, CA 92093-0424 United States;
Dr., La Jolla,, San Diego, CA 92093-0424 United
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41C-05
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 2102 Corotating streams, 2111 Ejecta, driver gases,
and magnetic clouds, 2139 Interplanetary shocks,
2164 Solar wind plasma, 7513 Coronal mass ejections
Bibliographic Code: 2003AGUFMSH41C..05T
Abstract
Interplanetary scintillation (IPS) measurements are known as one of
remote-sensing techniques which enable us to gain access to global
features of the solar wind (e.g. quasi-stationary corotating structures,
transient streams associated with CMEs). We have carried out a long-term
collaboration on the reconstruction of the heliospheric features from
IPS measurements made with the 327 MHz four-station system of the
Solar-Terrestrial Environment Laboratory (STEL), Nagoya University.
Under the collaboration, we have developed the computer-assisted
tomography (CAT) analysis method, which allows us to retrieve the 3D
distribution of the solar wind velocity and density from IPS data. We
also have been making the real-time reconstruction experiment of
heliospheric features using STEL IPS data and the CAT method. Based on
these results, we propose here the joint observations of IPS and SMEI.
The SMEI is a powerful tool to investigate the global heliospheric
features, and its capability is complementary to one of IPS
observations; That is, SMEI observations provide a high-resolution image
of the solar wind density distribution, while IPS observations provide
reliable estimates of the solar wind velocity. Therefore, a combination
of IPS and SMEI observations is essential for achieving a precise
reconstruction of global heliospheric (velocity and density) features by
the CAT analysis.
Title: SMEI: First Results and Future Capabilities
Authors: Webb, D. F.; Mozer, J. B.; Radick, R. R.;
Johnston, J. C.; Price, S. D.; Kuchar, T.;
Mizuno, D. R.; Jackson, B. V.; Buffington, A.;
Tappin, S. J.; Simnett, G. M.
Affiliation: AA(ISR, Boston College, 140 Commonwealth Ave.,
Chestnut Hill, MA 02467-3863 United States; Air
Force Research Lab, Space Vehicles Directorate, 29
Randolph Road, Hanscom AFB, MA 01731-3010 United
Research Lab, Space Vehicles Directorate, Sacramento
Peak Obs., Sunspot, NM 88349 United States; ),
AC(Air Force Research Lab, Space Vehicles
Directorate, Sacramento Peak Obs., Sunspot, NM 88349
United States; ), AD(Air Force Research Lab, Space
Vehicles Directorate, 29 Randolph Road, Hanscom
AFB, MA 01731-3010 United States; ), AE(Air Force
Research Lab, Space Vehicles Directorate, 29
Randolph Road, Hanscom AFB, MA 01731-3010 United
States; ), AF(ISR, Boston College, 140 Commonwealth
Ave., Chestnut Hill, MA 02467-3863 United States;
Air Force Research Lab, Space Vehicles Directorate,
29 Randolph Road, Hanscom AFB, MA 01731-3010 United
States; ), AG(ISR, Boston College, 140 Commonwealth
Ave., Chestnut Hill, MA 02467-3863 United States;
Air Force Research Lab, Space Vehicles Directorate,
29 Randolph Road, Hanscom AFB, MA 01731-3010 United
States; ), AH(CASS, University of California - San
Diego, La Jolla, CA 92093-0424 United States; ),
AI(CASS, University of California - San Diego, La
Jolla, CA 92093-0424 United States; ),
AJ(Astrophysics and Space Research Group, University
of Birmingham, Edgbaston, Birmingham, B15 2TT
United Kingdom; ), AK(Astrophysics and Space
Research Group, University of Birmingham, Edgbaston,
Birmingham, B15 2TT United Kingdom; )
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41C-03
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 2111 Ejecta, driver gases, and magnetic clouds, 2164
Solar wind plasma, 7513 Coronal mass ejections
Bibliographic Code: 2003AGUFMSH41C..03W
Abstract
The Solar Mass Ejection Imager (SMEI) experiment was launched on the STP
Coriolis mission 6 January 2003 and is now recording all-sky, white
light images on each 101-minute orbit. SMEI is fixed to the spacecraft
and views the sky above Earth using sunlight-rejecting baffles and CCD
camera technology. When fully calibrated, sky maps of structures having
enhanced electron density in the inner heliosphere will be routinely
produced. We will present some preliminary results of the early analysis
of SMEI data. These include observations of several dozen coronal mass
ejections (CMEs) as confirmed by the SOHO LASCO coronagraphs. One of
these was a halo event which propagated to and beyond 1 AU and was
associated with a major geomagnetic storm at Earth. Tomographic
techniques are being developed to analyze the SMEI observations of the
heliospheric plasma, including the transient CMEs and corotating
interaction regions. SMEI also detected Comet NEAT inbound to and
outbound from the Sun and the asteroid Vesta. With SMEI data we also can
study solar and solar wind processes, and the experiment is capable of
observing various other astronomical phenomena, such as variable stars,
the Zodiacal light, near-Earth objects and extrasolar planetary
transits.
Title: The Solar Mass Ejection Imager (SMEI)
Authors: Simnett, G. M.; Eyles, C. J.; Cooke, M. P.;
Waltham, N. R.; King, J. M.; Jackson, B. V.;
Buffington, A.; Hick, P. P.; Holladay, P. E.;
Anderson, P. A.
Affiliation: AA(School of Physics and Astronomy, University of
Birmingham, Birmingham, B15 2TT United Kingdom;
Astronomy, University of Birmingham, Birmingham, B15
AC(School of Physics and Astronomy, University of
Birmingham, Birmingham, B15 2TT United Kingdom;
Rutherford-Appleton Laboratory, Chilton, OX11 0QX
Science Dept., Rutherford-Appleton Laboratory,
Chilton, OX11 0QX United Kingdom;
Space Sciences, University of California at San
AG(Center for Astrophysics and Space Sciences,
University of California at San Diego, LaJolla, CA
Astrophysics and Space Sciences, University of
California at San Diego, LaJolla, CA 92093 ;
Laboratory/Space Vehicles Directorate (AFRL/VS),
Hanscom AFB, Bedford, MA 01731 ;
Boston University, Boston, MA 02467 ;
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41C-02
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 7513 Coronal mass ejections, 7531 Prominence
eruptions, 7594 Instruments and techniques
Bibliographic Code: 2003AGUFMSH41C..02S
Abstract
The Solar Mass Ejection Imager (SMEI) has been designed to detect and
forecast the arrival of solar mass ejections and other heliospheric
structures which are moving towards the Earth. We describe the
instrument, which was launched into a Sun-synchronous polar orbit on 6
January, 2003 on board the US DoD Coriolis spacecrafth. SMEI contains
three CCD cameras, sensitive over the optical waveband, each with a
field-of-view of 60 degrees x 3 degrees. The sensitivity is such that it
will detect changes in sky brightness equivalent to a tenth magnitude
star in one square degree of sky. Each camera takes an image every 4s
and the normal telemetry rate is 128 kbits/s. SMEI has a photometric
accuracy of around 0.1%. In addition to solar mass ejections, images of
stars and the zodiacal cloud are measured to this photometric accuracy
once/ orbit (102 minutes).
Title: IPS From LOFAR: A Complement to Thomson Scattering
Studies
Authors: Oberoi, D.; Kasper, J. C.; Lonsdale, C. J.;
Salah, J. E.; Lazarus, A. J.; Jackson, B. V.
Affiliation: AA(Haystack Observatory, Massachusetts Institute of
Technology, Off Route 40, Westford, MA 01886 United
Space Research, Massachusetts Institute of
Technology, 77, Massachusetts Avenue, Cambridge, MA
AC(Haystack Observatory, Massachusetts Institute of
Technology, Off Route 40, Westford, MA 01886 United
Observatory, Massachusetts Institute of Technology,
Off Route 40, Westford, MA 01886 United States;
Research, Massachusetts Institute of Technology, 77,
Massachusetts Avenue, Cambridge, MA 02139 United
Astrophysics and Space Sciences, University of
California at San Diego, 9500, Gilman Drive,
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41B-0463
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 6954 Radio astronomy, 6969 Remote sensing, 6982
Tomography and imaging, 6994 Instruments and
techniques
Bibliographic Code: 2003AGUFMSH41B0463O
Abstract
Information about the large scale physical properties of the inner
heliosphere plasma can only be obtained by employing remote sensing
techniques. The two most useful measurement techniques for this are
Thomson scattering, used by Solar Mass Ejection Imager (SMEI), and
Interplanetary Scintillation (IPS). Both these techniques are sensitive
to the distribution of properties of the solar wind plasma along the
entire line-of-sight through the medium. The two measurement techniques
are sensitive to different properties of the same physical plasma. IPS
is sensitive to the fluctuations in the refractive index of the medium
(~ delta ne2) and their spectral index, the
perpendicular component of velocity of the solar wind, the anisotropy in
electron density fluctuations caused by the magnetic field and their
inner scale. Thomson scattering, on the other hand, is sensitive only to
the distribution of the electron density along the line of sight. The
data from both these techniques are suitable for tomographic
reconstructions, yielding three dimensional visualisations of the inner
heliosphere. Heliospheric tomography will benefit significantly from the
denser sky coverage and the improved signal-to-noise IPS measurements
promised by the upcoming instruments and the simultaneous use of Thomson
scattering data. The unquestionable synergy between the information
obtained from these two techniques should be exploited to arrive at
significantly better constrained tomographic reconstructions. We are now
assessing the potential for space weather applications, including IPS
studies, of the Low Frequency Array (LOFAR), an aperture synthesis radio
interferometer covering the 10-240 MHz range. The unique design of this
instrument allows the possibility of high sensitivity observations of up
to 4000 IPS sources a day. This unprecedented ability will increase the
sampling of the inner heliosphere by ˜2 orders of magnitude
compared to the present IPS instruments and improve the signal-to-noise
of individual measurements. This paper will describe some aspects of the
LOFAR design and outline its potential IPS measurement capabilities.
Title: Space Performance of the Multistage Labyrinthine
SMEI Baffle
Authors: Buffington, A.; Jackson, B. V.; Hick, P. P.
Affiliation: AA(UCSD/CASS, Mail Code 0424 9500 Gilman Drive, La
Jolla, CA 92093-0424 United States;
0424 9500 Gilman Drive, La Jolla, CA 92093-0424
Mail Code 0424 9500 Gilman Drive, La Jolla, CA
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41B-0459
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 8194 Instruments and techniques
Bibliographic Code: 2003AGUFMSH41B0459B
Abstract
The Solar Mass Ejection Imager (SMEI) was launched on 6 January 2003,
and shortly thereafter raised to a nearly circular orbit at 840 km.
Three SMEI CCD cameras on the zenith-oriented CORIOLIS spacecraft cover
most of the sky beyond about 20° from the Sun, each 102-minute
orbit. Data from this instrument will ultimately provide precision
visible-light photometric sky maps. Once starlight and other constant or
slowly varying backgrounds are subtracted, the residue is mostly
sunlight that has been Thomson-scattered from heliospheric electrons.
These maps will enable 3-dimensional tomographic reconstruction of
heliospheric density and velocity. This analysis requires 0.1%
photometry and background-light reduction below one S10 (the brightness
equivalent of a 10th magnitude star per square degree). Thus
10-15 of surface-reduction is required relative to the solar
disk. The SMEI labyrinthine baffle provides roughly 10-10 of
this reduction; the subsequent optics provides the remainder. We analyze
data covering a range of angles between the SMEI optical axis and the
Sun, or the Moon, to evaluate the full system's stray-light rejection
performance.
Title: Interactive Visualization of Transient Solar Wind
Phenomena for Space Weather Applications
Authors: Wang, C. X.; Hick, P. P.; Jackson, B. V.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093-0424 ;
Space Sciences, University of California at San
Diego, La Jolla, CA 92093-0424 ;
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41B-0458
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 2102 Corotating streams, 2111 Ejecta, driver gases,
and magnetic clouds, 2194 Instruments and
techniques, 7513 Coronal mass ejections, 7594
Instruments and techniques
Bibliographic Code: 2003AGUFMSH41B0458W
Abstract
We present a volume rendering system developed for the visualization and
manipulation of 3D heliospheric volume data such as solar wind density,
velocity and magnetic field. Our system exploits the capabilities of the
VolumePro 1000 board from TeraRecon, Inc., a low-cost 64-bit PCI board
capable of rendering a 512-cubed array of volume data in real time at up
to 30 frames per second on a standard PC. Many operations have been
implemented such as stereo/perspective views, animations of
time-sequences, and determination of CME volumes and masses. We will
show examples of three-dimensional heliospheric volumes from
tomographic reconstructions of density and velocity using real-time
interplanetary scintillation (IPS) data. In the near future we expect
to add reconstructions based on the all-sky observations from the
recently launched Solar Mass Ejection Imager and employ our system to
interactively analyze and visualize the abundant information embedded in
these data.
Title: The Solar Mass Ejection Imager (SMEI) Mission
Authors: Jackson, B. V.; Buffington, A.; Hick, P. P.;
Holladay, P.; Johnston, J. C.; Kahler, S. W.;
Mozer, J.; Price, S.; Radick, R. R.; Sinclair, D.;
Simnett, G. M.; Eyles, C. J.; Cooke, M. P.;
Tappin, J.; Waltham, N. R.; Kuchar, T.; Mizuno, D.;
Webb, D. F.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093-0424 ;
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093-0424 ;
Laboratory, Space Vehicles Directorate, (AFRL, VS)
Force Research Laboratory, Space Vehicles
Research Laboratory, Space Vehicles Directorate,
AI(Air Force Research Laboratory, Space Vehicles
Research Laboratory, Space Vehicles Directorate,
Research, University of Birmingham, Birmingham,, UK
AM(School of Physics and Space Research, University
Physics and Space Research, University of
Department, Rutherford-Appleton Laboratory,
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#SH41B-0457
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 2102 Corotating streams, 2164 Solar wind plasma,
2194 Instruments and techniques, 7513 Coronal mass
ejections, 7594 Instruments and techniques
Bibliographic Code: 2003AGUFMSH41B0457J
Abstract
We have designed, built and launched into near-Earth orbit a Solar Mass
Ejection Imager (SMEI) capable of observing sunlight that has
Thomson-scattered from heliospheric structures of time-varying density.
SMEI is designed to observe heliospheric structures such as coronal mass
ejections, corotating structures and shock waves, to elongations greater
than 90° from the Sun. The instrument was inspired by the
heliospheric imaging capability demonstrated by the zodiacal light
photometers of the Helios spacecraft. The instrument makes effective
use of in situ solar wind data from spacecraft in the vicinity of the
imager by extending observations to the surrounding environment and back
to the Sun. A near-Earth imager can provide up to three days warning of
the arrival of a mass ejection from the Sun. In combination with other
imaging instruments in deep space, or alone by making some simple
assumptions about the outward flow of the solar wind, SMEI can provide a
tomographic analysis of the heliospheric structures surrounding it.
Title: Characteristics of Saturn's Atmosphere from
Ground-Based Thermal Infrared Remote Sensing
Authors: Orton, G. S.; Fisher, B.; Yanamandra-Fisher, P.;
Baines, K.; Ressler, M.; Beach-Kimball, B.;
Jackson, B.; Gezari, D.; Varosi, F.
Affiliation: AA(Jet Propulsion Laboratory, 4800 Oak Grove Drive,
Pasadena, CA 91109 United States;
Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109
AC(Jet Propulsion Laboratory, 4800 Oak Grove Drive,
Pasadena, CA 91109 United States;
Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109
Propulsion Laboratory, 4800 Oak Grove Drive,
Pasadena, CA 91109 United States;
University, Wesleyan Station, Middletown, CT 06459
United States; ), AG(Georgia Institute of
Technology, 219 Uncle Heine Way, Atlanta, GA 30032
United States; ), AH(NASA Goddard Space Flight
Center, Code 685, Greenbelt, MD 20771 United
States; ), AI(Univeristy of Florida, Department of
Astronomy, Gainesville, FL 32611 United States; )
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#P51C-0465
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE, 5700
PLANETOLOGY: FLUID PLANETS, 5704 Atmospheres:
composition and chemistry, 5757 Remote sensing
Bibliographic Code: 2003AGUFM.P51C0465O
Abstract
Several years of observations of Saturn, obtained primarily at NASA's
Infrared Telescope Facility, establish a baseline against which data
from the Cassini Composite Infrared Spectrometer (CIRS) and other
remote-sensing instruments can be compared. Thermal emission at 5.2 mu
m, sensitive to clouds near and above the 2--3 bar level, finds them to
be strikingly inhomogeneous with large zonal variations near the
equator and 45oS. At longer wavelengths, stratospheric
temperatures near 10 mbar are sensed by 7.85-mu m CH4
emission and (with C2H6 abundance variations
sensed by 12.2 mu m C2H6 emission). Trosospheric
temperatures near 100--400 mbar are sensed by H2
collision-induced emission between 17 and 24 mu m. Strong seasonal
forcing of stratospheric temperatures is evident, with temperatures
tracking the insolation variations with little time delay, inconsistent
with purely radiative equilibrium condistions. Stratospheric
temperature (or C2H6 abundance) peaked sharply
poleward of 81oS latitude in a high-resolution Keck image in
1998. Meridional variations of stratospheric and tropospheric
temperature are not strongly correlated with one another.
Planetary-scale zonal waves as large as 1 Kelvin amplitude are seen in
the stratospheric temperature field, with some evidence for even
larger-amplitude waves in the troposphere. Similar to vortices in Titan
and Jupiter, we might expect Cassini to detect a polar vortex (e.g. a
region of depressed temperatures with a sinusoidal boundary), if driven
by the seasonal loss of insolation poleward of its arctic circle. This
work was supported by funds from NASA to the Jet Propulsion Laboratory,
California Institute of Technology and the Goddard Space Flight Center.
Brett Beach-Kimball was supported by the Undergraduate Student
Researcher Program (USRP); Brian Jackson was supported by JPL as a
Caltech Summer Undergraduate Research Fellow.
Title: Application of Flow Field Flow Fractionation-ICP-MS
for the Study of Uranium Binding in Cell Suspensions
of Shewanella oneidensis
Authors: Jackson, B.; Seaman, J.; Neal, A.; Ranville, J.
Affiliation: AA(Savannah River Ecology Laboratory, University of
Georgia PO Drawer E, Aiken, SC 29802 United States;
Laboratory, University of Georgia PO Drawer E,
AC(Savannah River Ecology Laboratory, University of
Georgia PO Drawer E, Aiken, SC 29802 United States;
Department of Chemistry & Geochemistry, Golden, CO
Publication: American Geophysical Union, Fall Meeting 2003,
abstract \#B51C-0966
Publication Date: 12/2003
Origin: AGU
AGU Keywords: 1065 Trace elements (3670), 1094 Instruments and
techniques
Abstract Copyright: (c) 2003: American Geophysical Union
Bibliographic Code: 2003AGUFM.B51C0966J
Abstract
Field flow fractionation (FFF) is an aqueous size-based separation
technique applicable to the separation of biomolecules, colloids, and
bacteria. When interfaced on-line with ICP-MS detection, elemental data
can be collected concurrently. In this study we employed hyperlayer-
FFF methodology to separate cells of Shewanella oneidensis strain MR-1
from exopolymers present in washed cell suspensions. The cell
suspension was injected into a thin channel through which a carrier
solution (10mM NH4Cl) is continuously pumped. A field is
applied perpendicular to the direction of channel flow forcing the cells
and other particles against an accumulation wall; in this case we used
flow (Fl) FFF, where the perpendicular force is another fluid flow,
known as the cross flow, pumped across two porous frits on either side
of the channel. The cells experience hydrodynamic lift forces moving
them from the accumulation wall into faster flowing zones within the
laminar channel flow. Because these lift forces depend on particle
diameter, size separation takes place as the cells flow down the
channel. With a channel flow of 4 ml.min-1 and a cross flow
of 0.4 ml. min-1 the cells eluted with a retention time of
5.2 minutes corresponding to an approximate equivalent spherical cell
diameter of 1-2 æm based on calibration of the hyperlayer method
with sized polystyrene beads. Cell suspensions were spiked with
increasing concentrations of U to establish an adsorption isotherm and
with fixed U concentrations at varying pH to establish a pH sorption
isotherm. Elution of cells was detected by UV absorbance and the eluant
exiting the UV detector was interfaced on-line to ICP-MS to detect U. A
linear sorption isotherm was determined for U solution concentrations
from 0.2 - 16 æM. The pH sorption isotherm showed maximum U
sorption to S. oneidensis occurs at pH 5, in agreement with other batch
sorption studies. A relatively large molecular compound, presumably a
cell exudate, since the cells were determined to remain intact with
microscopy, was identified by FFF (soluble constituents are not retained
in hyperlayer FFF and thus elute in the void volume). This cell exudate
complexed U and at higher pH the exudate appeared to have a greater
affinity for U than the cell surface. Thus Fl-FFF interfaced with
ICP-MS detection appears to be a powerful analytical technique for metal
sorption studies with bacteria; analysis can be carried out on very
small sample volumes (typical injection volume is 25 æL) and
additional speciation information can be gained because soluble organic
constituents of the cell suspension also elute from the FFF channel and
are resolved from the cells. Other possible applications of Fl-FFF
include competitive metal binding studies in mixed bacteria suspensions
and mixed mineral-bacteria suspensions.
Title: Ultraviolet Lightcurve Internet Database of Active
Galactic Nuclei
Authors: Dunn, J.; Crenshaw, D. M.; Jackson, B.
Affiliation: AA(Georgia State University), AB(Georgia State
University), AC(Georgia Tech University)
Publication: American Astronomical Society Meeting 203, \#55.15;
Bulletin of the American Astronomical Society, Vol.
35, p.1298
Publication Date: 12/2003
Origin: AAS
Bibliographic Code: 2003AAS...203.5515D
Abstract
Using the Multimission Archives at Space Telescope (MAST), we have
extracted lightcurve information on 182 Seyfert Galaxies that have been
observed with the International Ultraviolet Explorer (IUE) and the Faint
Object Spectrograph (FOS). These lightcurves have been determined in two
different wavelength regions of the spectrum, ranging from 1100 /AA -
3000 /AA, using the SWP, LWR, and the LWP cameras on IUE and the G130H,
G190H, and G270H gratings of FOS. We measured small regions (between 25
/AA and 100 /AA) of the spectrum's continuum flux, taken in the rest
frame of the observed galaxy, to describe the flux level of a galaxy at
various points in time. The data we have extracted and basic principle
information provided by the NASA Extragalactic Database (NED) will be
made available via the Internet.
Title: The Solar Mass Ejection Imager (Smei)
Authors: Eyles, C. J.; Simnett, G. M.; Cooke, M. P.;
Jackson, B. V.; Buffington, A.; Hick, P. P.;
Waltham, N. R.; King, J. M.; Anderson, P. A.;
Holladay, P. E.
Affiliation: AA(School of Physics and Space Research, University
of Birmingham, B15 2TT, U.K. ), AB(School of Physics
and Space Research, University of Birmingham, B15
2TT, U.K. ), AC(School of Physics and Space
Research, University of Birmingham, B15 2TT, U.K. ),
AD(Center for Astrophysics and Space Science,
University of California, San Diego, CA 92093-0424,
U.S.A. ), AE(Center for Astrophysics and Space
Science, University of California, San Diego, CA
92093-0424, U.S.A. ), AF(Center for Astrophysics and
Space Science, University of California, San Diego,
CA 92093-0424, U.S.A. ), AG(Space Science
Department, Rutherford-Appleton Laboratory, Chilton,
OX11 0QX, U.K. ), AH(Space Science Department,
Rutherford-Appleton Laboratory, Chilton, OX11 0QX,
U.K. ), AI(Astronomy Department, Center for Space
Physics, Boston University, Boston, MA, U.S.A. ),
AJ(Air Force Research Laboratory/VSBS, 29, Randolph
Road, Hanscom AFB, MA 01731-3010, U.S.A. )
Publication: Solar Physics, v. 217, Issue 2, p. 319-347 (2003).
Publication Date: 11/2003
Origin: KLUWER
Bibliographic Code: 2003SoPh..217..319E
Abstract
We describe an instrument (SMEI) which has been specifically designed to
detect and forecast the arrival of solar mass ejections and other
heliospheric structures which are moving towards the Earth. Such events
may cause geomagnetic storms, with resulting radiation hazards and
disruption to military and commercial communications; damage to
Earth-orbiting spacecraft; and also terrestrial effects such as surges
in transcontinental power transmission lines. The detectors are
sensitive over the optical wave-band, which is measured using CCD
cameras. SMEI was launched on 6 January 2003 on the Coriolis spacecraft
into a Sun-synchronous polar orbit as part of the US DoD Space Test
Programme. The instrument contains three cameras, each with a field of
view of 60°×3°, which are mounted onto the spacecraft such
that they scan most of the sky every 102-min orbit. The sensitivity is
such that changes in sky brightness equivalent to a tenth magnitude star
in one square degree of sky may be detected. Each camera takes an image
every 4 s. The normal telemetry rate is 128 kbits s-1. In
order to extract the emission from a typical large coronal mass
ejection, stellar images and the signal from the zodiacal dust cloud
must be subtracted. This requires accurate relative photometry to 0.1%.
One consequence is that images of stars and the zodiacal cloud will be
measured to this photometric accuracy once per orbit. This will enable
studies of transient zodiacal cloud phenomena, flare stars, supernovae,
comets, and other varying point-like objects.
Title: An Algorithm for Optimal Partitioning of Data on an
Interval
Authors: Jackson, Brad; Scargle, Jeffrey D.; Barnes, David;
Arabhi, Sundararajan; Alt, Alina; Gioumousis, Peter;
Gwin, Elyus; Sangtrakulcharoen, Paungkaew;
Tan, Linda; Tsai, Tun Tao
Publication: eprint arXiv:math/0309285
Publication Date: 09/2003
Origin: ARXIV
Keywords: Mathematics - Numerical Analysis, Astrophysics,
Computer Science - Computational Engineering,
Finance, and Science, Computer Science - Data
Structures and Algorithms, Computer Science -
Information Theory, Mathematics - Combinatorics,
65C60
Comment: 3 pages, 1 figure, submitted to IEEE Signal
Processing Letters, revised version with added
references
Bibliographic Code: 2003math......9285J
Abstract
Many signal processing problems can be solved by maximizing the fitness
of a segmented model over all possible partitions of the data interval.
This letter describes a simple but powerful algorithm that searches the
exponentially large space of partitions of $N$ data points in time
$O(N^2)$. The algorithm is guaranteed to find the exact global optimum,
automatically determines the model order (the number of segments), has a
convenient real-time mode, can be extended to higher dimensional data
spaces, and solves a surprising variety of problems in signal detection
and characterization, density estimation, cluster analysis and
classification.
Title: Time-dependent tomography of heliospheric structures
using IPS and Thomson scattering observations
Authors: Jackson, Bernard V.; Hick, P. P.; Buffington, A.
Publication: In: Solar variability as an input to the Earth's
environment. International Solar Cycle Studies
(ISCS) Symposium, 23 - 28 June 2003, Tatranská
Lomnica, Slovak Republic. Ed.: A. Wilson. ESA
SP-535, Noordwijk: ESA Publications Division, ISBN
92-9092-845-X, 2003, p. 823 - 833
Publication Date: 09/2003
Origin: ARI
ARI Keywords: Heliosphere: Structures
Abstract Copyright: ESA
Comment: ISBN: 92-9092-845-X
Bibliographic Code: 2003ESASP.535..823J
Abstract
The Air Force/NASA Solar Mass Ejection Imager (SMEI) launched January 6,
2003 is now recording whole sky data on each 100-minute orbit. Precise
photometric images of the heliosphere around Earth are expected from
these data. To optimize the information available from this and similar
instruments, we are developing a tomographic technique for analyzing
remote sensing observations of the heliosphere using both interplanetary
scintillation (IPS) and Thomson scattering data. The technique provides
a three-dimensional reconstruction of heliospheric velocities and
densities. We have refined our tomography program to analyze
time-dependent phenomena such as evolving corotating heliospheric
structures and more discrete events such as coronal mass ejections
(CMEs).
Title: Time-dependent tomography of hemispheric features
using interplanetary scintillation (IPS)
remote-sensing observations
Authors: Jackson, B. V.; Hick, P. P.; Buffington, A.;
Kojima, M.; Tokumaru, M.; Fujiki, K.; Ohmi, T.;
Yamashita, M.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, LaJolla, CA),
AB(Solar-Terrestrial Environment Laboratory, Nagoya
University, Japan), AC(), AD(), AE(), AF(), AG(),
AH()
Publication: SOLAR WIND TEN: Proceedings of the Tenth
International Solar Wind Conference. AIP Conference
Proceedings, Volume 679, pp. 75-78 (2003).
Publication Date: 09/2003
Origin: STI
Keywords: solar wind, computerised tomography, remote sensing,
solar corona
DOI: 10.1063/1.1618545
Bibliographic Code: 2003AIPC..679...75J
Abstract
We have developed a Computer Assisted Tomography (CAT) program that
modifies a time-dependent three-dimensional kinematic heliospheric model
to fit interplanetary scintillation (IPS) observations. The tomography
program iteratively changes this global model to least-squares fit IPS
data. The short time intervals of the kinematic modeling (~1 day) force
the heliospheric reconstructions to depend on outward solar wind motion
to give perspective views of each point in space accessible to the
observations, allowing reconstruction of interplanetary Coronal Mass
Ejections (CMEs) as well as corotating structures. We show these models
as velocity or density Carrington maps and remote views. We have studied
several events, including the July 14, 2000 Bastille-day halo CME. We
check our results by comparison with additional remote-sensing
observations, and observations from near-Earth spacecraft.
Title: Landau damping in trapped Bose condensed gases
Authors: Jackson, B.; Zaremba, E.
Affiliation: AA(Department of Physics, Queen's University,
Kingston, ON K7L 3N6, Canada
Physics, Queen's University, Kingston, ON K7L 3N6,
Publication: New Journal of Physics, Volume 5, Issue 1, pp. 88
(2003).
Publication Date: 07/2003
Origin: IOP
DOI: 10.1088/1367-2630/5/1/388
Bibliographic Code: 2003NJPh....5...88J
Abstract
We study Landau damping in dilute Bose Einstein condensed gases in both
spherical and prolate ellipsoidal harmonic traps. We solve the
Bogoliubov equations for the mode spectrum in both of these cases, and
calculate the damping by summing over transitions between excited
quasiparticle states. The results for the spherical case are compared to
those obtained in the Hartree Fock (HF) approximation, where the
excitations take on a single-particle character, and excellent agreement
between the two approaches is found. We have also taken the
semiclassical limit of the HF approximation and obtain a novel
expression for the Landau damping rate involving the time-dependent
self-diffusion function of the thermal cloud. As a final approach, we
study the decay of a condensate mode by making use of dynamical
simulations in which both the condensate and thermal cloud are evolved
explicitly as a function of time. A detailed comparison of all these
methods over a wide range of sample sizes and trap geometries is
presented.
Title: Pre-Cassini Infrared Characterization of Saturn's
Atmosphere
Authors: Orton, G.; Fisher, B.; Yanamandra-Fisher, P.;
Baines, K.; Ressler, M.; Beach-Kimball, B.;
Jackson, B.; Gezari, D.; Varosi, F.
Affiliation: AA(JPL/Caltech), AB(JPL/Caltech), AC(JPL/Caltech),
AD(JPL/Caltech), AE(JPL/Caltech), AF(Wesleyan U.),
AG(Georgia Inst. Tech.), AH(Goddard Space Flight
Ctr.), AI(U. florida)
Publication: American Astronomical Society, DPS meeting \#35,
\#50.04; Bulletin of the American Astronomical
Society, Vol. 35, p.1018
Publication Date: 05/2003
Origin: AAS
Bibliographic Code: 2003DPS....35.5004O
Abstract
We report 23 years of infrared remote sensing observations of Saturn,
primarily at the NASA Infrared Telescope Facility to establish a
long-term baseline against which Cassini remote-sensing observations can
be compared. Cloud structure is constrained by near-infrared reflected
sunlight, where images reveal stratospheric haze between -11 and +18
degrees planetocentric latitude, but not at the poles (unlike Jupiter).
Thermal emission at 5.2 microns senses clouds near 2-3 bars which are
strikingly inhomogeneous spatially, with large zonal variations near the
equator and 45 degrees S. Stratospheric temperatures near 10 mbar are
sensed by 7.85-micron CH4 emission and (with
C2H6 abundance variations) by 12.2-micron
C2H6 emission. Tropospheric temperatures near
100-400 mbar are sensed by H2 collision-induced emission
between 17 and 24 microns. Strong seasonal forcing of stratospheric
temperatures is evident, with temperatures tracking the insolation
variations with a several-year delay. A target-of-opportunity
observation on a Keck engineering night in 1998 shows a strong peak of
stratospheric temperature (or CH2H6 abundance)
poleward of 81degrees S latitude. Just as for Jupiter, meridional
variations of stratospheric and tropospheric temperatures are not
correlated with one another. Planetary-scale zonal waves as large as 1
Kelvin amplitude are seen in the stratospheric temperature field, with
some evidence for even larger-amplitude waves in the troposphere.
Cassini may detect an arctic region of depressed temperatures with a
non-uniform southern boundary, if a polar vortex, similar to those in
Titan and Jupiter, is driven by the seasonal loss of insolation north of
its arctic circle.
This work was supported by funds from NASA to JPL and GSFC. Brett
Beach-Kimball was supported by the Undergraduate Student Researcher
Program (USRP); Brian Jackson was supported by JPL as a Caltech Summer
Undergraduate Research Fellow (SURF).
Title: Identification and representability of processes
controlling unsaturated flow in vegetated soils at
differing temporal scales
Authors: Butler, A. P.; Jackson, B. M.
Publication: EGS - AGU - EUG Joint Assembly, Abstracts from the
meeting held in Nice, France, 6 - 11 April 2003,
abstract \#11565
Publication Date: 04/2003
Origin: EGU
Bibliographic Code: 2003EAEJA....11565B
Abstract
A model describing unsaturated flow in vegetated soil has been
developed, coupling plant feedback mechanisms with a finite-difference
implementation of Richards' equation. While care has been taken to
relate all parameters and processes to physically realistic analogies,
moderate uncertainty in a range of parameters is unavoidable due to the
need for characterisation of pedo-transfer functions and the complexity
of plant water processes. Confidence in model effectiveness has been
addressed through simulations of lysimeter experiments undertaken at
Imperial College. A highly comprehensive data set consists of
measurements on eight lysimeters divided into two sets of four, with the
two sets containing different soil types. The water table was maintained
at 65 cm below the soil surface, and all possessed a mature crop of
perennial ryegrass (Lolium perenne L.) by the start of the experiment.
Measurements of soil hydrological status and onsite meteorological data
were taken about every quarter of an hour for a period of close to a
year, providing detailed information on events within the lysimeters,
and the impact of various meteorological conditions over the year.
Diurnal variation and seasonal responses are particularly clear. An
application of sensitivity and uncertainty analysis to the model, using
this detailed data set, has been undertaken. In the performance of the
optimisation process, good quality of model definition at both diurnal
and seasonal scales is treated as particularly important, as is the
effect of measurement error on parameterisation at these different
scales. Since we are correcting parameter estimates in the presence
of measurement error, it is important to have an understanding of the
distortions produced on the outputs by noise. Therefore, a Bayesian
framework is used to facilitate the treatment of both measurement and
parametric errors, and to allow the inclusion of subjective probability
without losing mathematical rigour. Metropolis Hastings Monte-Carlo
methods are used to approximate the posterior distribution for
parameters of interest. Due to the complicated topology of the posterior
probability, a range of different heuristic algorithms, including
simulated annealing, has been investigated in order to aid the search
for hard to find modes in which the posterior achieves substantial local
maxima. Examination of such maxima aids in addressing questions of
parameter and overall model identifiability.
Title: Characterization of Complex Colloidal Suspensions
Authors: Seaman, J. C.; Guerin, M.; Jackson, B. P.;
Ranville, J. M.
Publication: EGS - AGU - EUG Joint Assembly, Abstracts from the
meeting held in Nice, France, 6 - 11 April 2003,
abstract \#7553
Publication Date: 04/2003
Origin: EGU
Bibliographic Code: 2003EAEJA.....7553S
Abstract
Surface chemical reactions play a major role in controlling contaminant
fate and transport in the subsurface environment. Recent field and
laboratory evidence suggests that mobile soil and groundwater colloids
may facilitate the migration of sparingly soluble groundwater
contaminants. Colloidal suspensions collected in the field or generated
in laboratory column experiments tend to be fairly dilute in nature and
comprised of relatively small particulates (<1mum) with significant
net charge and relatively high surface areas. Researchers have readily
applied sophisticated analytical techniques that were previously
reserved for studying ideal systems to the characterization of mobile
colloids. However, many of these analytical techniques, including
total/selective dissolution methods, dynamic light scattering,
micro-electrophoresis, streaming potential, and even scanning electron
microscopy (SEM), can be biased in of larger size fractions, and
therefore, extremely sensitive to sampling, storage, and fractionation
artifacts. In addition, surface modifiers such as sorbed oxides or
organics can alter particulate appearance, composition, and behavior
when compared to synthetic analogues or mineral standards. The current
presentation will discuss the limitations and inherent biases associated
with a number of analytical characterization techniques that are
commonly applied to the study of mobile soil and groundwater colloids,
including field flow fractionation (FFF) and acoustic based methods that
have only recently become available.
Title: Can we learn anything new from the animal's
perspective?: Bayesian stimulus estimation based on
neural spike trains
Authors: Jackson, B. Scott
Publication: Acoustical Society of America Journal, Volume 113,
Issue 4, pp. 2197-2197 (2003).
Publication Date: 04/2003
Origin: STI
Bibliographic Code: 2003ASAJ..113.2197J
Abstract
The classical approach to understanding a neural coding scheme is to
characterize spike trains elicited by multiple presentations of the same
stimulus, an example being the rate-intensity function. However, the
task for the organism is deciphering the stimulus content from spike
trains elicited by single stimulus presentations, a process that is more
analogous to Bayesian stimulus estimation. The usefulness of Bayesian
stimulus estimation in the neural context, using the auditory periphery
as a model system, was investigated. More specifically, the encoding of
stimulus intensity in the spike rate of single primary auditory neurons
was examined. It was found that the results of this method are heavily
influenced by the a priori stimulus distribution and that apparent
benefits of this approach, such as linearization and, in some instances,
increased stimulus dynamic range, are offset by concomitant
disadvantages, such as increased estimation error and decreased stimulus
dynamic range in other instances. Hence, in this context, Bayesian
stimulus estimation does not contribute meaningful additional knowledge
to our understanding of neural coding, and these results suggest that
related methodologies, such as stimulus reconstruction and information
theoretic methods, be used and interpreted with caution. [Work supported
by Syracuse University and NIH Grant 5-P01-DC000380.]
Title: Non-equilibrium blister formation in lipid bilayer -
bilayer junctions
Authors: Parthasarathy, Raghuveer; Jackson, Bryan;
Lowery, Thomas; Wong, Amy; Groves, Jay T.
Affiliation: AA(University of California, Berkeley) AB(University
of California, Berkeley) AC(University of
California, Berkeley) AD(University of California,
Berkeley) AE(University of California, Berkeley and
Lawrence Berkeley National Laboratory)
Publication: American Physical Society, Annual APS March Meeting
2003, March 3-7, 2003, , abstract \#A9.005
Publication Date: 03/2003
Origin: APS
Bibliographic Code: 2003APS..MAR.A9005P
Abstract
Lipid bilayers form the structural basis of cell membranes, as well as
the environment in which membrane biochemical events occur. The emerging
study of interactions between reconstituted lipid bilayers, therefore,
promises simple experimental models for intercellular interactions. Even
in bilayer-bilayer junctions composed only of simple lipids, however,
many aspects of structure formation remain poorly understood. For
example, non-uniform adhesion can result, taking the form of
"blisters" of separation between the adhering membranes. We
explore the formation and stabilization of these blisters, making use of
recently developed fluorescence resonance energy transfer and
interference microscopy techniques that allow nanometer-scale
topographic imaging. We observe that blister formation is triggered by
rapid adhesion often induced by osmotic shock, and is not contingent on
electrostatic reorganization. We propose a hydrodynamic model for
blister stability, in which the non-equilibrium blister shapes are
prohibited from relaxing due to the impedance of viscous water flow.
Title: Introduction of the CSSS magnetic field calculation
into the UCSD tomographic solar wind model
Authors: Dunn, Tamsen; Hick, Pierre P.; Jackson, Bernard V.;
Zhao, Xuepu
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA)), AD(Stanford Univ.
(USA))
Publication: Innovative Telescopes and Instrumentation for Solar
Astrophysics. Edited by Stephen L. Keil, Sergey V.
Avakyan. Proceedings of the SPIE, Volume 4853, pp.
504-510 (2003).
Publication Date: 02/2003
Origin: SPIE
Bibliographic Code: 2003SPIE.4853..504D
Abstract
Tomographic techniques developed at UCSD over the last few years
incorporate a kinematic model of the solar wind to determine and
forecast the large-scale three-dimensional extents of velocity and
density using interplanetary scintillation (IPS) observations or Thomson
scattering brightness data. In this paper, we introduce magnetic field
calculations from the Stanford Current-Sheet Source Surface (CSSS) model
into our kinematic model. The CSSS model is used to extrapolate the
photospheric magnetic field to a source surface at 15 solar radii
(Rs). The UCSD kinematic model convects magnetic field from
15 Rs out to and beyond Earth. We compare the results with in
situ data near Earth. The spatial relationship between the heliospheric
current sheet and coronal mass ejections (CMEs) is shown in remote views
of the inner heliosphere
Title: Calculations for and laboratory measurements of a
multistage labyrinthine baffle for SMEI
Authors: Buffington, Andrew; Jackson, Bernard V.;
Hick, Pierre P.
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA))
Publication: Innovative Telescopes and Instrumentation for Solar
Astrophysics. Edited by Stephen L. Keil, Sergey V.
Avakyan. Proceedings of the SPIE, Volume 4853, pp.
490-503 (2003).
Publication Date: 02/2003
Origin: SPIE
Bibliographic Code: 2003SPIE.4853..490B
Abstract
The spaceborne Solar Mass Ejection Imager (SMEI) is scheduled for launch
into near-earth orbit (>800 km) in early 2003. Three SMEI CCD cameras
on the zenith-oriented CORIOLIS spacecraft cover most of the sky each
100-minute orbit. Data from this instrument will provide precision
visible-light photometric maps. Once starlight and other constant or
slowly varying backgrounds are subtracted, the residue is mostly
sunlight that has Thomson-scattered from heliospheric electrons. These
maps will enable 3-dimensional tomographic reconstruction of
heliospheric density and velocity. The SMEI design provides three
cameras, one of which views to within 18 degrees of the solar disk with
a field of view 60° long by 3° wide. Placed end-to-end, three
fields of view then cover a nearly 180° long strip that sweeps out
the sky over each orbit. The 3-dimensional tomographic analysis requires
0.1% photometry and background-light reduction below one S10 (the
brightness equivalent of a 10th magnitude star per square degree). Thus
10-15 of surface-brightness reduction is required relative to
the solar disk. The SMEI labyrinthine baffle provides roughly 10-10
of this reduction; the subsequent optics provides the remainder.
We describe the baffle design and present laboratory measurements of
prototypes that confirm performance at this level.
Title: Time-dependent tomography of heliospheric features
using the three-dimensional reconstruction
techniques developed for the solar mass ejection
imager (SMEI)
Authors: Jackson, Bernard V.; Hick, Pierre P.;
Buffington, Andrew
Affiliation: AA(Univ. of California/San Diego (USA)), AB(Univ. of
California/San Diego (USA)), AC(Univ. of
California/San Diego (USA))
Publication: Innovative Telescopes and Instrumentation for Solar
Astrophysics. Edited by Stephen L. Keil, Sergey V.
Avakyan. Proceedings of the SPIE, Volume 4853, pp.
23-30 (2003).
Publication Date: 02/2003
Origin: SPIE
Bibliographic Code: 2003SPIE.4853...23J
Abstract
Precise photometric images of the heliosphere are expected from the Air
Force/NASA Solar Mass Ejection Imager (SMEI) now scheduled for launch in
February 2003, and the all-sky cameras proposed for other NASA missions.
To optimize the information available from these instruments, we are
developing tomographic techniques for analyzing remote sensing
observations of heliospheric density as observed in Thomson scattering
(e.g. using the Helios photometer data) for eventual use with SMEI. We
have refined the tomography program to enable us to analyze
time-dependent phenomena, such as the evolution of corotating
heliospheric structures and more discrete events such as coronal mass
ejections. Both types of phenomena are discerned in our data, and are
reconstructed in three dimensions. We use our tomography technique to
study the interaction of these phenomena as they move outward from the
Sun for several events that have been studied by multiple spacecraft in
situ observations and other techniques.
Title: Eley-Rideal reactions of H atoms with Cl adsorbed on
Au(111): Quantum and quasiclassical studies
Authors: Quattrucci, Joseph G.; Jackson, Bret;
Lemoine, Didier
Affiliation: AA(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003),
AB(Department of Chemistry, University of
Massachusetts, Amherst, Massachusetts 01003),
AC(Laboratoire de Physique des Lasers, Atomes et
Molécules, UMR CNRS 8523, Centre d'Etudes et de
Recherches Lasers et Applications, Université de
Lille 1, Bâtiment P5, 59655 Villeneuve d'Ascq Cedex,
France)
Publication: Journal of Chemical Physics, Volume 118, Issue 5,
pp. 2357-2366 (2003).
Publication Date: 02/2003
Origin: AIP
Keywords: surface chemistry, density functional theory,
potential energy surfaces, wave functions,
adsorption, atom-atom reactions, hydrogen neutral
atoms, chlorine, reaction kinetics theory
Abstract Copyright: (c) 2003: American Institute of Physics.
DOI: 10.1063/1.1533735
Bibliographic Code: 2003JChPh.118.2357Q
Abstract
The Eley-Rideal reactions of H atoms with Cl adsorbed on Au(111)
surfaces are examined. Electronic structure calculations based on
density functional theory are used to construct a model potential energy
surface. Both quantum and quasiclassical methods are used to compute
reaction cross sections and product state distributions. Steering of the
incident H atom towards the adsorbed Cl leads to relatively large
reaction cross sections of 2-3 Å2. The product HCl in this
strongly exothermic reaction has over an eV of energy in vibrational
motion, and a bit less than one eV each in rotation and translation.
Title: The 3d Solar Wind Over the Solar Cycle Observed by
IPS
Authors: Kojima, Masayoshi; Jackson, Bernard V.;
Ohmi, Tomoaki; Hick, Paul; Hayashi, Keiji;
Tokumaru, Munetoshi; Fujiki, Ken-Ichi
Affiliation: AA(Solar-Terrestrial Environment Laboratory, Nagoya
University), AB(Center for Astrophysics & Space
Sciences, University of California, San Diego),
AC(Solar-Terrestrial Environment Laboratory, Nagoya
University), AD(Center for Astrophysics & Space
Sciences, University of California, San Diego),
AE(W.W.Hansen Experimental Physics Laboratory,
Stanford University), AF(Solar-Terrestrial
Environment Laboratory, Nagoya University),
AG(Solar-Terrestrial Environment Laboratory, Nagoya
University)
Publication: The Sun and the Heliosphere as an Integrated System,
25th meeting of the IAU, Joint Discussion 7, 17 July
2003, Sydney, Australia
Publication Date: 00/2003
Origin: IAU
Bibliographic Code: 2003IAUJD...7E..25K
Abstract
The interplanetary scintillation (IPS) method can observe the dynamics
and structure of the solar wind in three dimensions with a relatively
short time cadence. Because IPS observations are line-of-sight
integrations we have developed an IPS tomography analysis method that
can retrieve three-dimensional solar wind parameters as well as provide
better spatial resolutions than previous IPS techniques. Using the IPS
tomography analysis we have studied the solar cycle dependence of the
solar wind properties such as the velocity of fast solar wind bimodal
structure north-south asymmetry of fast wind and the origin of a compact
slow streamer. Solar wind structure is bimodal not only in the solar
minimum phase but also in the ascending and descending phases; In solar
minimum phase a small coronal hole in vicinity of an active region
emanates slow wind and a polar coronal hole also becomes the source of
slow wind when it shrinks to a small size at solar maximum; the velocity
of the fast wind does not change significantly when a coronal hole
changes its size in the descending and ascending phases. We also
introduce the three-dimensional dynamic nature of interplanetary
transient events that were observed with another new technique:
time-dependent tomography.
Title: Tomography of Heliospheric Features Developed for
Smei
Authors: Jackson, Bernard V.; Hick, P. P.; Buffington, Andrew
Affiliation: AA(Center for Astrophysics and Space Sciences-0424),
AB(Center for Astrophysics and Space Sciences-0424),
AC(Center for Astrophysics and Space Sciences-0424)
Publication: The Sun and the Heliosphere as an Integrated System,
25th meeting of the IAU, Joint Discussion 7, 17 July
2003, Sydney, Australia
Publication Date: 00/2003
Origin: IAU
Bibliographic Code: 2003IAUJD...7E..23J
Abstract
The Air Force/NASA Solar Mass Ejection Imager (SMEI) launched January 6
2003 is now recording whole sky data on each 100-minute orbit. Precise
photometric images of the heliosphere around Earth are expected from
these data. To optimize the information available from this and similar
instruments we are developing a tomographic technique for analyzing
remote sensing observations of the heliosphere as observed in Thomson
scattering. The technique provides three-dimensional reconstructions of
heliospheric density. We have refined our tomography program to analyze
time-dependent phenomena such as evolving corotating heliospheric
structures and more discrete events such as coronal mass ejections
(CMEs).
Title: Eley--Rideal and hot atom reactions between H atoms
on metal and graphite surfaces
Authors: Jackson, B.
Publication: The Chemical Physics of Solid Surfaces, vol. 11, pp.
51-77
Publication Date: 00/2003
Origin: CROSSREF
DOI: 10.1016/S1571-0785(03)11003-6
Bibliographic Code: 2003CPSS...11...51J
Abstract
Not Available
Title: Corotational Tomography of Heliospheric Features
Using Global Thomson Scattering Data
Authors: Jackson, Bernard V.; Hick, P. Paul
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at), AB(San Diego, La
Jolla, CA, U.S.A. )
Publication: Solar Physics, v. 211, Issue 1, p. 345-356 (2002).
Publication Date: 12/2002
Origin: KLUWER
Bibliographic Code: 2002SoPh..211..345J
Abstract
The Air Force/NASA Solar Mass Ejection Imager (SMEI) will provide
two-dimensional images of the sky in visible light with high (0.1%)
photometric precision, and unprecedented sky coverage and cadence. To
optimize the information available from these images they must be
interpreted in three dimensions. We have developed a Computer Assisted
Tomography (CAT) technique that fits a three-dimensional kinematic
heliospheric model to remotely-sensed Thomson scattering observations.
This technique is designed specifically to determine the corotating
background solar wind component from data provided by instruments like
SMEI. Here, we present results from this technique applied to the Helios
spacecraft photometer observations. The tomography program iterates to a
least-squares solution of observed brightnesses using solar rotation,
spacecraft motion and solar wind outflow to provide perspective views of
each point in space covered by the observations. The corotational
tomography described here is essentially the same as used by Jackson et
al. (1998) for the analysis of interplanetary scintillation (IPS)
observations. While IPS observations are related indirectly to the solar
wind density through an assumed (and uncertain) relationship between
small-scale density fluctuations and density, Thomson scattering physics
is more straightforward, i.e., the observed brightness depends linearly
on the solar wind density everywhere in the heliosphere. Consequently,
Thomson scattering tomography can use a more direct density-convergence
criterion to match observed Helios photometer brightness to brightness
calculated from the model density. The general similarities between
results based on IPS and Thomson scattering tomography validate both
techniques and confirm that both observe the same type of solar wind
structures. We show results for Carrington rotation 1653 near solar
minimum. We find that longitudinally segmented dense structures corotate
with the Sun and emanate from near the solar equator. We discuss the
locations of these dense structures with respect to the heliospheric
current sheet and regions of activity on the solar surface.
Title: Efficient Eley-Rideal Reactions of H Atoms with
Single Cl Adsorbates on Au(111)
Authors: Lemoine, Didier; Quattrucci, Joseph G.;
Jackson, Bret
Affiliation: Laboratoire de Physique des Lasers, Atomes et
Molécules, UMR CNRS 8523, Centre d'Etudes et de
Recherches Lasers et Applications, Université de
Lille 1, Bâtiment P5, 59655 Villeneuve d'Ascq CEDEX,
France
Publication: Physical Review Letters, vol. 89, Issue 26, id.
268302
Publication Date: 12/2002
Origin: APS
Abstract Copyright: (c) 2002: The American Physical Society
DOI: 10.1103/PhysRevLett.89.268302
Bibliographic Code: 2002PhRvL..89z8302L
Abstract
Density functional theory is used to construct an interaction model for
H atoms with Cl over Au(111). Single-adsorbate Eley-Rideal reactions are
investigated with quantum and quasiclassical methods. The reaction cross
sections, amounting to 2-3 Å2, are much larger than for
HD recombinations on metals. This can be traced to the adsorbed Cl being
relatively far above the surface, the H-Cl interaction prevailing over
the H-substrate attraction for a sizable range of impact parameters.
Title: Visualization of Remotely-Sensed Heliospheric
Plasmas
Authors: Bailey, M.; Hick, P. P.; Wang, C.; Jackson, B. V.;
Buffington, A.
Affiliation: AA(San Diego Supercomputer Center, University of
California at San Diego, La Jolla, CA 92093 United
and Space Sciences, University of California at San
Diego, La Jolla, CA 92093 United States;
Space Sciences, University of California at San
Diego, La Jolla, CA 92093 United States;
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Astrophysics and Space Sciences, University of
California at San Diego, La Jolla, CA 92093 United
Publication: American Geophysical Union, Fall Meeting 2002,
abstract \#SH21A-0511
Publication Date: 12/2002
Origin: AGU
AGU Keywords: 2102 Corotating streams, 2111 Ejecta, driver gases,
and magnetic clouds, 2134 Interplanetary magnetic
fields, 2194 Instruments and techniques, 7594
Instruments and techniques
Bibliographic Code: 2002AGUFMSH21A0511B
Abstract
We demonstrate a software application designed for the display and
real-time manipulation of 3D heliospheric volume data, such as solar
wind density, velocity and magnetic field. The software exploits the
capabilities of the Volume Pro 1000 (from TeraRecon, Inc.), a low-cost
64-bit PCI board capable of rendering a 512-cubed array of volume data
in real time at up to 30 frames per second on a standard PC. The
application allows stereo and perspective views, and animations of
time-sequences. We show several examples of three-dimensional
heliospheric volume data derived from tomographic reconstructions based
on heliospheric remote sensing observations of the heliospheric density
and velocity structure (e.g. Thomson scattering and interplanetary
scintillation observations). This work was supported through NASA grant
NAG5-9423 and Air Force MURI grant F49620-01-0359.
Title: Halo CME's - Will They Hit or Miss Earth?
Authors: Jackson, B. V.; Hick, P. P.; Buffington, A.
Affiliation: AA(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AB(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
AC(Center for Astrophysics and Space Sciences,
University of California at San Diego, La Jolla, CA
Publication: American Geophysical Union, Fall Meeting 2002,
abstract \#SH21A-0474
Publication Date: 12/2002
Origin: AGU
AGU Keywords: 2111 Ejecta, driver gases, and magnetic clouds, 2164
Solar wind plasma, 7513 Coronal mass ejections, 7594
Instruments and techniques, 7894 Instruments and
techniques
Bibliographic Code: 2002AGUFMSH21A0474J
Abstract
To optimize the information from maps of the sky that cover large
elongations we have developed a Computer Assisted Tomography (CAT)
program that models these using a time-dependent three-dimensional
heliospheric model to fit Thomson scattering or STELab (Nagoya
University) interplanetary scintillation (IPS) observations. The
duration of a CME event (typically several days) imposes the restriction
that the reconstruction model primarily uses outward solar wind motion
to give perspective views of each point in space. The results to date
are commensurate with the observational coverage, temporal and spatial
resolution, and signal to noise available from the original data. We
provide remote observer views of IPS-based reconstructions of halo CMEs
also observed by the LASCO coronagraphs. We practice our modeling
techniques by making these views available in real time to forecast halo
CME Earth-arrival. Here we explore the locations and shapes of a few
select halo CMEs and their three-dimensional velocity structure in order
to determine whether they will hit or miss the Earth. This work is
supported by NASA grant NAG5-8504 and AFOSR grant F49620-01-1-0054.
Title: Remote-Sensing of the Solar Wind: A Space Weather
Application
Authors: Hick, P. P.; Rappoport, S. A.; Jackson, B. V.;
Dunn, T.; Wang, C.
Affiliation: AA(CASS/UCSD), AB(CASS/UCSD), AC(CASS/UCSD),
AD(CASS/UCSD), AE(CASS/UCSD)
Publication: American Astronomical Society Meeting 201, \#141.02;
Bulletin of the American Astronomical Society, Vol.
35, p.567
Publication Date: 12/2002
Origin: AAS
Bibliographic Code: 2002AAS...20114102H
Abstract
Remote sensing observations of the solar wind in the inner heliosphere
fill an observational gap between near-Sun remote sensing and near-Earth
in-situ data. We use heliospheric tomography to follow solar
disturbances from Sun to Earth as the basis for a real-time space
weather system. Over the past few years interplanetary scintillation
observations from the Solar-Terrestrial Laboratory at Nagoya University,
Japan, were the main source of data. In the near future Thomson
scattering observations from the recently launched Solar Mass Ejection
Imager (SMEI) will be added.
Here we show some recent developments in the visualization techniques
used to process the volume data sets produced by the tomographic
analyis: solar wind density, velocity and magnetic field. 3D
visualization is based on an image rendering engine written in the IDL
programming language. In addition, we use hardware-based volume
rendering with the Volume Pro PCI board from TeraRecon. This board
renders 4D volume data (three spatial, plus the time dimension) in
real-time, allowing interactive manipulation of evolving
(time-dependent) data sets.
This work was supported through NASA grant NAG5-9423 and Air Force MURI
grant F49620-01-0359.
Title: Coronal Mass Ejections Identified in Interplanetary
Scintillation (IPS) Tomography and in LASCO
Coronagraph Images
Authors: Rappoport, S. A.; Hick, P. P.; Jackson, B. V.
Affiliation: AA(CASS/UCSD), AB(CASS/UCSD), AC(CASS/UCSD)
Publication: American Astronomical Society, 201st AAS Meeting,
\#83.03; Bulletin of the American Astronomical
Society, Vol. 34, p.1242
Publication Date: 12/2002
Origin: AAS
Bibliographic Code: 2002AAS...201.8303R
Abstract
Coronal mass ejections (CMEs), including halo CMEs, can be observed in
interplanetary scintillation (IPS) data. To optimize the information
from radio source observations, we model them using a time-dependent
three-dimensional tomography program. We depict this heliospheric model
as a series of "sky map" images that cover elongations extending from 10
to 80 degrees. These IPS maps show CMEs observed earlier in the LASCO
coronagraph images with approximately the same shapes and extents that
were seen closer to the Sun. Here, a series of these CME events,
including halo CMEs, are mapped as they move outward to distances as
great as 1 AU.
Title: Adsorption of hydrogen and deuterium atoms on the
(0001) graphite surface
Authors: Zecho, Thomas; Guttler, Andreas; Sha, Xianwei;
Jackson, Bret; Kuppers, Jurgen
Affiliation: AA(Max-Planck-Institut fur Plasmaphysik (Euratom
Association), 95748 Garching), AB(Experimentalphysik
III, Universitat Bayreuth), AC(Department of
Chemistry, University of Massachusetts),
AD(Department of Chemistry, University of
Massachusetts), AE(Max-Planck-Institut fur
Plasmaphysik (Euratom Association), 95748 Garching)
Publication: The Journal of Chemical Physics, vol. 117, iss. no.
18, p. 8486-8492
Publication Date: 11/2002
Category: Solid-State Physics
Origin: STI
NASA/STI Keywords: ADSORPTION, AUGER EFFECT, DESORPTION, DEUTERIUM,
ELECTRON ENERGY, ELECTRONS, ENERGY DISSIPATION,
ENERGY SPECTRA, GRAPHITE, HIGH RESOLUTION, HYDROGEN,
HYDROGEN ATOMS, KINETICS, POTENTIAL ENERGY, THERMAL
ENERGY
Comment: NASA/STI Accession number: 20020080577
DOI: 10.1063/1.1511729
Bibliographic Code: 2002JChPh.117.8486Z
Abstract
Adsorption of H and D on HOPG surfaces was studied with thermal
desorption (TDS), electronic (ELS), and high-resolution
electron-energy-loss (HREELS) spectroscopies. After admission of H (D)
from thermal (2000 K) atom sources to clean graphite surfaces TD spectra
revealed recombinative molecular H2 (D2)
desorption in a main peak around 445 K (490 K) and a minor peak at 560 K
(580 K). After admission of higher fluences the main peak shifts to 460
K (500 K) and develops a shoulder at 500 K (540 K). The saturation
coverages were calculated as 0.4plus-or-minus0.2 for H and D and initial
sticking coefficients of 0.4plus-or-minus0.2 were obtained. Throug