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Author name code: laming
ADS astronomy entries on 2022-09-14
author:Laming, Martin
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Title: Powerful Diagnostics of Cosmic-Ray Modified Shock by Hα
Polarimetry
Authors: Shimoda, J.; Laming, M.
2022icrc.confE.140S Altcode: 2022PoS...395E.140S
No abstract at ADS
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Title: The Origin of the Crab Nebula
Authors: Temim, Tea; Blair, William P.; Drissen, Laurent; Fox,
Ori Dosovitz; Laming, J. Martin; Lyutikov, Maxim; Martin, Thomas;
Milisavljevic, Dan; Modjaz, Maryam; Rest, Armin; Sankrit, Ravi; Slane,
Patrick; Smith, Nathan; Strolger, Louis-Gregory; Sukhbold, Tuguldur
2021jwst.prop.1714T Altcode:
We propose NIRCam and MIRI imaging and MIRI MRS spectroscopy of
the iconic Crab Nebula in order to test models of the progenitor and
explosion mechanism by mapping the dust distribution, imaging the iron
emission, measuring Ni/Fe ratios, and searching for dust compositional
variations. The imaging requested will permit us to separate the bright
line and synchrotron emission from dust emission and produce the first
complete mapping of the dust distribution in the Crab Nebula. The
[Fe II] emission will be used to study the spatial distribution of Fe
in the remnant and derive its total mass. The MIRI MRS spectra will be
used to measure the Ni/Fe ratios across the filaments and determine the
dust composition at two positions that may have different ejecta and
swept-up circumstellar contributions. These observational measurements
can elucidate differences in predictions for the two competing explosion
mechanisms for the Crab's progenitor (electron capture vs. Fe-core
collapse) and determine whether a dense circumstellar medium, possibly
distributed in a disk around the progenitor, has been important in
shaping the Crab Nebula as it is observed today. The total requested
time for the program is 22.57 hours.
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Title: Linking the Sun to the heliosphere using composition data
and modelling: coronal jets as a test case
Authors: Wimmer-Schweingruber, Robert F.; Parenti, Susanna; Del Zanna,
G.; Edmondson, J.; Giunta, A.; Hansteen, V. H.; Higginson, A.; Lepri,
S.; Laming, M.; Lynch, B. J.; von Steiger, R. E.; Wiegelmann, T.;
Zambrana Prado, N.
2019shin.confE.231W Altcode:
Understanding the formation and evolution of the solar wind is still
a priority in the Solar and Heliospheric communities. We expect
a significant progress in terms of observations with the upcoming
Solar Orbiter mission (launch in 2020), which will provide detailed
in-situ measurements of the solar wind and several remote-sensing
observations. However, real progress will only be possible if we
improve our understanding of the physical link between what measured
in-situ and its source regions on the Sun. In this respect, the plasma
chemical and charge-state compositions are considered good diagnostic
tools. In this paper we present results obtained from an extensive team
work aiming at providing solid diagnostics for linking the in-situ and
the remote sensing measurements. For our test cases, we selected two
periods when a single active region produced, close to its sunspot,
jets which had a counterpart signature in the Heliosphere in the form
of type-III radio bursts. These jets therefore marked magnetically
open regions expanding in the heliosphere. Firstly, we looked for
signatures of the open field associated with the active regions in
in-situ data from ACE and WIND, finding potential tracers. Secondly,
we studied the magnetic topology of the full Sun and Heliosphere with
extrapolations of photospheric data and MHD modeling. We found that
the open field area is consistent with the source and evolution of the
jets, as observed with EUV imagers (SDO/AIA, STEREO/EUVI). Thirdly, we
analysed remote sensing EUV spectroscopic observations to measure the
plasma conditions (densities, temperatures and chemical composition)
whenever available. We then modeled the solar wind and charge
state evolution with the solar distance along the open fields to
establish a link between the in-situ signatures and the remote sensing
observations. We discuss the various difficulties associated with such
studies, and highlight how Solar Orbiter measurements can improve them.
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Title: Exploring the Properties of Transverse Waves at the Base of
the Solar Wind
Authors: Weberg, Micah J.; Morton, Richard; McLaughlin, James; Laming,
Martin; Ko, Yuan-Kuen
2019shin.confE.173W Altcode:
Transverse (or ‘Alfvénic’) waves are commonly invoked by
theories and models to explain coronal heating and solar wind
acceleration. However, direct measurements are sparse and most of
what we know is derived from indirect proxies for wave activity. In
this study, we present a large, statistical study of transverse waves
directly observed in coronal plumes between May 2010 and May 2019
by SDO / AIA. The data was processed using an automated version of
the Northumbria University Wave Tracking Code (NUWT) and presents a
detailed picture of wave properties at the base of the solar wind. We
find that the bulk wave parameters within the time periods analysed
are largely consistent over most of a solar cycle. However, there is
some evidence for smaller-scale variations with height, latitude, and
over time periods of a few years. We will also explore the possibility
of frequency-dependant processes which may give limits on the height
at which wave dissipation, and thereby solar wind acceleration,
begins. Lastly, we will give estimates for the total energy flux
contained in the waves and discuss how it compares to the energy
required to accelerate the solar wind.
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Title: Element Abundances and Solar Wind Origins
Authors: Laming, Martin
2019shin.confE..29L Altcode:
We examine the different element abundances exhibited by the closed
loop solar corona and the slow speed solar wind. Both are subject
to the First Ionization Potential (FIP) Effect, the enhancement in
coronal abundance of elements with FIP below 10 eV (e.g. Mg, Si,
Fe) with respect to high FIP elements (e.g. O, Ne, Ar), but with
subtle differences. Intermediate elements, S, P, and C, with FIP
just above 10 eV, behave as high FIP elements in closed loops, but
are fractionated more like low FIP elements in the solar wind. On
the basis of FIP fractionation by the ponderomotive force in the
chromosphere, we discuss fractionation scenarios where this difference
might originate. Fractionation low in the chromosphere where hydrogen
is neutral enhances the S, P and C abundances. This arises with
nonresonant waves, which are ubiquitous in open field regions, and
is also stronger with torsional Alfven waves, as opposed to shear
(i.e. planar) waves. We discuss the bearing these findings have on
models of interchange reconnection as the source of the slow speed solar
wind. The outflowing solar wind must ultimately be a mixture of the
plasma in the originally open and closed fields, and the proportions
and degree of mixing should depend on details of the reconnection
process. We also describe novel diagnostics in ultraviolet and extreme
ultraviolet spectroscopy now available with these new insights, with
the prospect of investigating slow speed solar wind origins and the
contribution of interchange reconnection by remote sensing.
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Title: The Correlation Between The Enhanced Sulfur Abundance in Slow
Solar Winds and The Magnetic Field Geometry of Their Source Regions
Authors: Kuroda, Natsuha; Laming, Martin
2019shin.confE...9K Altcode:
We present an examination of the First Ionization Potential (FIP)
fractionation scenario by the ponderomotive force in the chromosphere
by using observations from The Solar Wind Ion Composition Spectrometer
(SWICS) on board The Advanced Composition Explorer (ACE). Based on the
prediction of the ponderomotive force model by Laming et al. (2019)
that the abundance enhancements of intermediate FIP elements, S, P, and
C, in slow solar wind can be explained by the release of plasma from
strong open fields, much stronger than those usually associated with
fast wind source regions, we examine the possible correspondence between
the enhanced fractionation of intermediate FIP elements in slow solar
winds and the magnetic field strength of their source regions. We do so
by surveying the extensive record of solar wind speeds and composition
from the ACE mission, and investigating the magnetic feature on the Sun
associated with the repeated sulfur abundance anomaly corresponding
to the decrease in the solar wind speed, found over about four solar
rotation cycles in the beginning of 2008. We also obtain rough profiles
of the magnetic field strength at the source regions of these slow
winds, estimate the fractionation values of various elements using
the ponderomotive force model with the field profiles as inputs,
and compare the results with the observed fractionation values."
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Title: On the Detection of Coronal Suprathermal Ions and their Role
as Seeds for SEP Production
Authors: Laming, Martin; Strachan, Leonard; Tun, Sam; Ko, Yuan-Kuen;
Socker, Dennis; Brown, Charles; Provornikova, Elena; Moses, Dan
2016shin.confE...7L Altcode:
We review the problem of understanding the variability in Solar
Energetic Particle (SEP) events, wherein two ostensibly similar CMEs can
have very different SEP characteristics. A number of lines of evidence
suggest that the presence or absence of a population of suprathermal
ions in the corona, known as seed particles, is the determining factor,
and that monitoring this population could lead to forecasts of SEP
events. We discuss an observational technique designed to solve this
problem by detecting suprathermal seed particles as extended wings
on spectral lines, and describe an experiment designed for a flight
opportunity on the DoD Space Test Program, due for launch in 2019.
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Title: Waves at Oblique Shocks and the Highest Cosmic Ray Energies
in Tychos SNR
Authors: Laming, Martin
2015xrvw.confE..10L Altcode:
We describe a new model for the stripes of synchrotron radiation seen in
the remnant of Tychos supernova, in terms of Alfven wave generation by
the Bell Instability, followed by reflection, refraction and damping at
an oblique shock. Based on estimates for damping rates due to turbulent
cascade and transit time damping, we estimate the dependence of the
visibility of the stripes on the shock obliquity, and determine a
maximum cosmic ray energy in Tychos SNR in the range 6 x 1014 - 1
x 1015 eV, close to the knee in the cosmic ray spectrum. With such
an understanding, synchrotron stripes ought in principle to be more
commonly seen in SNRs, and should constitute a prime science topic
for any future X-ray astronomy observatory.
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Title: X-ray Surveyor Discussion Session Results from the X-ray
Vision Workshop
Authors: Allured, Ryan; Arenberg, Jonathan; Bogdan, Akos; Canning,
Rebecca; Churazov, Eugene; Civano, Francesca; Clarke, Tracy; Corrales,
Lia; Di Matteo, Tiziana; Elvis, Martin; Fabbiano, Giuseppina; Falcone,
Abe; Garcia, Javier; Gaskin, Jessica; Goldman, Itzhak; Kargaltsev,
Oleg; Klinger, Noel; Laming, Martin; McNamara, Brian; Markevitch,
Maxim; Marshall, Herman; Mosquera, Ana; Mroczkowski, Anthony;
Natarajan, Priyamvada; Nielsen, Joey; Nowak, Michael; Ozel, Feryal;
Poppenhaeger, Katja; Porquet, Delphine; Randall, Scott; Schwartz,
Daniel; Swartz, Douglas A.; Temim, Tea; Van Weeren, Reinout; Weisskopf,
Martin; Zhuravleva, Irina; ZuHone, John A.
2015xrvw.confE...6A Altcode:
This paper summarizes the results of a brainstorming session held
during the X-ray Vision Workshop (Oct 6-8, 2015, Washington DC). The
workshop was convened to discuss the scientific potential of the X-ray
Surveyor mission. The X-ray Surveyor concept, which was defined by
the Astrophysics Roadmap, is to effect a 100-fold gain in survey and
spectroscopic capability over the Chandra X-ray Observatory, while
at least matching Chandra’s sub-arcsecond imaging capability.<BR />
This paper is intended to inform interested scientists of the growing
discussion in<BR /> our community and to solicit their input in the
area of new science that a next<BR /> generation high-resolution X-ray
Observatory may provide for astrophysics. This<BR /> paper is not an
official document and is certainly not the definitive science case
for an X-ray Surveyor mission. It is, instead, an early input to this
discussion, which we hope will lead to a full reference white paper
on the X-Ray Surveyor concept.
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Title: In search of the radio signatures on SEP-productive solar
active regions
Authors: Tun Beltran, Samuel D.; Laming, Martin
2015TESS....120322T Altcode:
Solar active regions may produce a wide variety of transients in
the meter-decameter wavelength range.Some of these bursts result
from mildly relativistic electron beams traveling along closed
(type I) or open (type III) magnetic field lines or from energized
electrons trapped in coronal magnetic fields (IV). The energization
of these electron populations may be achieved through magnetic field
reconnection. Reconnection may also be the driver which creates
populations of suprathermal electrons. These suprathermals are now
viewed as a prerequisite for the efficient production of solar energetic
particles through shock-driven acceleration. We here present work
done towards deriving a radio indicator for levels of reconnection
correlated with large SEP storms. Working mostly with data from the
Nançay Radioheliograph, spatio-spectral analysis is carried out
on SEP-rich AR and a control group that is not. We discuss the most
promising candidates of the sought after signature.
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Title: MHD Turbulence and the FIP Effect
Authors: Laming, Martin
2010APS..DPPPM0014L Altcode: 2010APS..DPPPM10014
The First Ionization Potential (FIP) Effect is the by now well known
abundance anomaly in the solar corona and slow speed solar wind,
where elements with FIP less than about 10 eV (e.g. Fe, Mg, Si) are
enhanced in abundance by a factor of about 3-4. High FIP elements
(e.g. C, O, Ar) are essentially unchanged, while the highest FIP
element, He, is depleted by a factor of about 0.5. A similar, though
reduced abundance anomaly is found in the fast speed solar wind, and in
coronal holes. These element fractionations are best explained by the
action of the ponderomotive force in the solar chromosphere, arising as
Alfvén waves reflect from the strong density gradients. Chromospheric
ions, but not neutrals, are preferentially accelerated upwards. I will
describe some recent developments, including the parametric generation
of slow mode waves by the Alfvén wave driver, that now allows both
the enhancement of Fe, Mg, S, etc, and the depletion of He to occur
simultaneously.
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Title: Analytic Approach to the Stability of Standing Accretion Shocks
Authors: Laming, Martin
2008APS..APR10HE03L Altcode:
We explore an analytic model of the accretion shock in the postbounce
phase of a core-collapse supernova explosion. We find growing
oscillations of the shock in the l=1 and 2 modes, in agreement with a
variety of existing numerical simulations. For modest values of the
ratio of the outer accretion shock to that of the inner boundary to
the shocked flow, the instability appears to derive from the growth
of trapped sound waves, whereas at higher values, postshock advection
clearly plays a role. Thus, the model described here may relate to the
different mechanisms of instability recently advocated by Blondin &
Mezzacappa and by Foglizzo and collaborators.
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Title: A Mechanism for Electron-Proton Temperature Equilibration in
Collisionless Shocks
Authors: Ghavamian, Parviz; Laming, M.; Rakowski, C. E.
2007AAS...210.4101G Altcode: 2007BAAS...39..154G
The analysis of Balmer-dominated optical spectra from non-radiative
(adiabatic) SNRs has shown that the ratio of the electron to proton
temperature at the blast wave is close to unity at shock speeds below
400 km/s, but declines sharply down to the the mass proportional value
(1/1836) at shock speeds exceeding 2000 km/s. We propose a physical
model for the heating of electrons and ions in non-cosmic ray dominated,
strong shocks (> 400 km/s) wherein the electrons are heated by
lower hybrid waves immediately ahead of the shock front. These waves
arise naturally from the cosmic ray pressure gradient upstream from
the shock. The model predicts a nearly constant level of electron
heating over a wide range of shock speeds, resulting in an inverse
square relationship between T(electon)/T(proton) and shock speed that
is fully consistent with the observations.
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Title: Jets and Asymmetries in the Cas A SNR
Authors: Laming, Martin
2006sgrb.confE..35L Altcode:
In April-May 2004 the instruments on the Chandra X-ray observatory
acquired an unprecedented deep integration of the Cassiopeia A supernova
remnant, for a total of 1 million seconds. I will present the results
of an initial analysis of the so-called "jet" regions of the remnants,
and review analyses of earlier data from the Chandra archive, with
a view to highlighting aspects of the explosion asymmetry that are
visible today in the morphology and spectra of the remnant. In
particular from x-ray spectroscopy, we can show that the "jets"
are indeed associated with asymmetry of the explosion as opposed to
asymmetry in the circumstellar medium, and start to place numbers on
the various parameters involved. We also make initial inferences on
asymmetries in the Fe/Si inner ejecta and their possible relation to
the direction of the compact central object natal kick.
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Title: Supernova and Gamma-Ray Burst Remnants
Authors: Chevalier, Roger; Hwang, Una; Laming, Martin
2006sgrb.confE....C Altcode:
The connection between Supernovae and Gamma-Ray Bursts has provided
insights to extend our understanding of both these phenomena beyond
what was known from studying them separately. A unique window into
the connections between the progenitors and mechanisms of supernova
and gamma-ray burst explosions is provided by their remnants. This
meeting brings together experts of the remnants of both Supernovae and
Gamma-Ray Bursts to combine this collective knowledge and to foster
productive communication between theorists and observers.
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Title: Electron Heating in the Solar Wind
Authors: Laming, M.
2005AGUSMSP51B..06L Altcode:
We report on progress in modeling the elevated charge states
observed in the fast solar wind with respect to the coronal hole
source region. Improvements include the incorporation of new atomic
data for dielectronic recombination of L-shell ions in our modeling,
following the recent work of Badnell and collaborators. A second issue
considered will be that of magnetic field inhomogeneity (as opposed
to plasma density inhomogeneity) as an agent of instability. High
temperature ions gyrating in curved magnetic field produce local
anisotropies in their velocity distribution function, which in turn
are unstable to the generation of lower hybrid waves. These waves
then damp by heating electrons, giving rise to the observed increase
in ion charge state. Work supported by NASA LWS NNH05AA05i and by the
NRL/ONR Solar Magnetism and the Earth's Environment 6.1 Research Option.
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Title: Instruments: ACIS - Science Highlights: Chandra Ms Observation
of Cassiopeia A
Authors: Hwang, Una; Laming, Martin
2005ChNew..12....7H Altcode:
No abstract at ADS
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Title: The FIP effect is solved!
Authors: Laming, M.
2004cosp...35.1145L Altcode: 2004cosp.meet.1145L
We discuss a further development of models along the lines originally
suggested by Schwadron, Fisk and Zurbuchen (1999). These authors
considered wave heated coronal loops where waves penetrate to loop
footpoints, heating ions but not neutrals. This gives rise to abundance
enhancements in elements which are ionized in the chromosphere
(i.e. low first ionization potential) over those which are neutral
through the higher ion scale height. Due to the low energy density
residing in waves which can resonate with ion gyrofrequencies, we
consider the effect of nonresonant waves through the ponderomotive
force they exert on ions. For a broad class of solutions, an upward
ponderomotive force exists on ions, and for quite reasonable wave energy
densities reproduces the observed solar FIP abundance enhancement
very well. Varying wave energy density varies the FIP enhancement,
and for certain special cases a downwards ponderomotive force on ions
may occur. The possible application of this to the inverse FIP effect
observed in highly active stellar coronae will be discussed. Work
supported by NASA Grant NAG5-9105, NASA Contract S13783G and by the
NRL/ONR Solar Magnetism and the Earth's Environment 6.1 Research Option.
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Title: Laser-plasma simulations of astrophysical phenomena and novel
applications to semiconductor annealing
Authors: Grun, J.; Laming, M.; Manka, C.; Donnelly, D. W.; Covington,
B. C.; Fischer, R. P.; Velikovich, A.; Khokhlov, A.
2003LPB....21..529G Altcode:
At the frontier of plasma physics and technology are applications of
laser-generated plasmas to laboratory simulations of astrophysical
phenomena and to industrial processing. This article presents work at
the Naval Research Laboratory in both of these areas. We show how laser
plasmas are used to measure a blast wave corrugation overstability
important in astrophysics. Detailed atomic physics calculations
of radiative cooling within the blast front are used to develop
a criterion of the existence of the overstability and are used to
explain the experimental results. The criterion depends on quantities
such as element abundances, densities, temperatures, and blast wave
velocities—quantities which can be measured spectroscopically—and
therefore used to infer whether astrophysical blast wave nonuniformities
are the result of this instability. In other experiments, high-velocity
jets are formed in the laboratory using miniature hollow cones. Jets
produced by these cones are used to study the physics of jets occurring
in supernovae and in star-forming accretion disks. In industrial
semiconductor processing, annealing, that is, removing crystal
damage and electrically activating the semiconductor, is a critical
step. Industrial annealing techniques most often utilize heat generated
by an oven, flash lamps, or a low-power laser. During such heating
dopants within the semiconductor lattice diffuse and spread. This
degrades the performance of circuits in which the individual circuit
elements are very close to each other. We are developing an annealing
technique in which shock or sound waves generated by a laser plasma
are used to anneal the semiconductor. We have demonstrated that the
method works over small areas and that it does not lead to significant
dopant diffusion.
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Title: EBIT diagnostics using X-ray spectra of highly ionized Ne
Authors: Matranga, Marco; Barbera, Marco; Maggio, Antonio; Peres,
Giovanni; Serio, Salvatore; Takács, Endre; Silver, Eric; Gillaspy,
John; Schnopper, Herbert; Laming, Martin; Beeman, Jeff; Haller, Eugen;
Madden, Norman
2003NIMPB.205..244M Altcode:
We have carried out a detailed analysis of highly ionized neon
spectra collected at the NIST EBIT using an NTD germanium X-ray
microcalorimeter developed at the Harvard-Smithsonian Center for
Astrophysics [Nucl. Instr. and Meth. A 444 (2000) 156]. Our attention
was focused especially on the Ne IX He-like triplet to check electron
density diagnostics through the intercombination/forbidden line
ratio. We have investigated possible effects of the ion dynamics on
the plasma emission line intensities, looking at the dependence of
the count-rate and the charge state distribution on the electron beam
energy and current. The temperature and spatial distribution of the
neon ions, and hence the overlap between the electron beam and the ion
cloud, depend on the electron beam operating parameters. The overlap
affects the average electron density seen by the ions, and in turn
the measured line ratio. These results underscore the value of future
improved studies of the trapped ion dynamics, both for understanding the
EBIT performance and for allowing experimenters to take full advantage
of its potential for astrophysical plasma diagnostics.
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Title: A synoptic spectral study of Cassiopeia-A based on XMM-Newton
and BeppoSax observations
Authors: Bleeker, Johan; Vink, Jacco; van der Heyden, Kurt; Willingale,
Dick; Kaastra, Jelle; Laming, Martin
2002astro.ph..2207B Altcode:
In this paper we present recent image and spectral data of Cas-A
obtained with XMM-Newton and BeppoSAX. Analysis of the hard X-ray
continuum does not support an interpretation of the hard X-radiation
as synchrotron emission produced in the primary shock, non-thermal
Bremsstrahlung is a plausible alternative. Moreover, a recent 500
kilosecond deep observation of the hard X-ray continuum by BeppoSAX has
revealed the positive detection of the 44Sc nuclear decay lines at 67.9
and 78.4 keV. Appropriate modelling of the hard X-ray continuum leads
to an estimate of the initial 44Ti mass of (0.8-2.5)E-4 solar masses. We
also present ionisation age, temperature, abundances maps. The observed
elemental abundance ratio patterns can be reconciled best with a
type Ib SNe, arising from a 60 solar mass progenitor (ZAMS) with
high-mass-loss. The accurate modeling of the image-resolved emission
line spectra has enabled us to derive reliable Doppler velocities for
the bright Si-K, S-K, and Fe-K line complexes.
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Title: Galactic abundances: Report of working group 3
Authors: Klecker, B.; Bothmer, V.; Cummings, A. C.; George, J. S.;
Keller, J. W.; Salerno, E.; Sofia, U. J.; Stone, E. C.; Thielemann,
F. -K.; Wiedenbeck, M. E.; Buclin, F.; Christian, E. R.; Flückiger,
E. O.; Hofer, M. Y.; Jones, F. C.; Kirilova, D.; Kunow, H.; Laming,
M.; Tranquille, C.; Wenzel, K. -P.
2001AIPC..598..207K Altcode: 2001sgc..conf..207K
We summarize the various methods and their limitations and strengths
to derive galactic abundances from in-situ and remote-sensing
measurements, both from ground-based observations and from instruments
in space. Because galactic abundances evolve in time and space it is
important to obtain information with a variety of different methods
covering different regions from the Very Local Insterstellar Medium
(VLISM) to the distant galaxy, and different times throughout the
evolution of the galaxy. We discuss the study of the present-day VLISM
with neutral gas, pickup ions, and Anomalous Cosmic Rays, the study of
the local interstellar medium (ISM) at distances <1.5 kpc utilizing
absorption line me asurements in H I clouds, and the study of galactic
cosmic rays, sampling contemporary (~15 Myr) sources in the local ISM
within a few kiloparsec of the solar system. Solar system abundances,
derived from solar abundances and meteorite studies are discussed
in several other chapters of this volume. They provide samples of
matter from the ISM from the time of solar system format ion, about
4.5 Gyr ago. The evolution of galactic abundances on longer time
scales is discussed in the context of nuclear synthesis in the various
contributing stellar objects. .
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Title: Laboratory Astrophysics Survey Of Key X-Ray Diagnostic Lines
Using A Microcalorimeter On An Electron Beam Ion Trap
Authors: Silver, E.; Schnopper, H.; Bandler, S.; Brickhouse, N.;
Murray, S.; Barbera, M.; Takacs, E.; Laming, M.; Kink, I.; Porto,
J.; Gillaspy, J. D.; Deslattes, R.; Hudson, L.; Madden, N.; Landis,
D.; Beeman, J.; Haller, E. E.
2000HEAD....5.4332S Altcode: 2000BAAS...32.1265S
Cosmic plasma conditions created in an Electron Beam Ion Trap (EBIT)
make it possible to simulate the dependencies of key diagnostic
x-ray lines on density, temperature, and excitation conditions
that exist in astrophysical sources. We used a microcalorimeter to
measure broad band spectra obtained from the NIST EBIT with an energy
resolution approaching that of a Bragg crystal spectrometer. Spectra
are presented for nitrogen, oxygen, neon, argon , and iron in various
stages of ionization.
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Title: Laboratory Astrophysics Survey Of Key X-Ray Diagnostic Lines
Using A Microcalorimeter On An Electron Beam Ion Trap
Authors: Silver, Eric; Schnopper, Herbert; Bandler, Simon; Brickhouse,
Nancy; Murray, Stephen; Barbera, Marco; Takacs, Endre; Laming, Martin;
Kink, Ilmar; Porto, Trey; Gillaspy, John; Deslattes, Richard; Hudson,
Larry; Madden, Norm; Landis, Don; Beeman, Jeffrey; Haller, Eugene
2000APS..DPPWO2003S Altcode:
Cosmic plasma conditions created in an Electron Beam Ion Trap (EBIT)
make it possible to simulate the dependencies of key diagnostic
x-ray lines on density, temperature, and excitation conditions
that exist in astrophysical sources. We used a microcalorimeter to
measure broad band spectra obtained from the NIST EBIT with an energy
resolution approaching that of a Bragg crystal spectrometer. Spectra
are presented for nitrogen, oxygen, neon, argon , and iron in various
stages of ionization.
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Title: Laboratory Astrophysics Survey Of Key X-Ray Diagnostic Lines
Using A Microcalorimeter On An Electron Beam Ion Trap
Authors: Silver, Eric; Schnopper, Herbert; Bandler, Simon; Brickhouse,
Nancy; Murray, Stephen; Barbera, Marco; Takacs, Endre; Gillaspy,
John D.; Porto, Trey; Kink, Ilmar; Madden, Norm; Landis, Don; Beeman,
Jeffrey; Haller, Eugene; Laming, Martin
2000APS..DMP..J602S Altcode:
Cosmic plasma conditions created in an Electron Beam Ion Trap (EBIT)
make it possible to simulate the dependencies of key diagnostic x-ray
lines on density, temperature, and excitation conditions that exist
in astrophysical sources. We used a microcalorimeter coupled with
an x-ray optic to measure broad band spectra obtained from the NIST
EBIT with an energy resolution approaching that of a Bragg crystal
spectrometer. Spectra are presented for nitrogen, oxygen, neon, argon ,
and iron in various stages of ionization.
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Title: Spectroscopic Study of the Galactic Supernova Remnant RCW 86
Authors: Smith, R. Chris; Ghavamian, Parviz; Long, Knox S.; Hartigan,
Pat; Raymond, John; Laming, Martin
1999noao.prop..350S Altcode:
We propose to undertake a detailed study of the supernova remnant
RCW 86 and its newly discovered Balmer-dominated filaments, involving
low-resolution, moderate-resolution and high-resolution spectroscopic
observations of both radiative and Balmer-dominated filaments. These
observations provide estimates of the reddening, shock velocity and
angle to the line of sight, and insights into the physics of Balmer-
dominated shocks. In addition, we will search for possible changes of
electron-ion equilibration around the remnant, which may be related
to the angle the shocks make with respect to the ambient magnetic
field. This spectroscopic dataset will be combined with the optical,
X-ray (ROSAT PSPC and HRI), and radio data we have in hand. Our
multiwavelength study will provide a better overall understanding of
the state of the remnant and its history (as the possible remnant of
SN 185 A.D.), as well as the physics of the shocks which define its
periphery. This is a resubmission of last year's proposal, for which
we were assigned time but lost most of the two runs due to bad weather.
