Résumés des programmes du Science Team de FUSE
(Programmes français)
Program ID Program Contact Program Title
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Major Programs
P101 Sembach The Properties of Hot Gas in the Milky Way and
Magellanic Clouds (Galactic Halo)
P102/P122 Sembach The Properties of Hot Gas in the Milky Way and
Magellanic Clouds (Galactic Disk)
P103/P203 Sembach The Properties of Hot Gas in the Milky Way and
Magellanic Clouds (Magellanic Clouds)
P104/P204 Sembach Deuterium Abundances and the D/H Ratio
(Local ISM)
P105/P205 Sembach Deuterium Abundances and the D/H Ratio
(Galactic Disk)
P106 Sembach Deuterium Abundances and the D/H Ratio
(Galactic Halo)
P107/207 Sembach Deuterium Abundances and the D/H Ratio
(Snapshot Survey)
P108 Sembach Deuterium Abundances and the D/H Ratio
(Extragalactic)
P109 Sembach Deuterium Abundances and the D/H Ratio
(Solar System)
P110/P210 Kriss FUSE Studies of the Intergalactic Medium
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FUSE Science Team Small and Medium Programs
P111 Kriss Active Galactic Nuclei
P112 Oegerle O VI in Cooling Flow Clusters
P113 Sonneborn Circumstellar Interaction in SN 1987A
P114 Blair Supernova Remnants
P115 Shull Diffuse Molecular Hydrogen
P116 Snow Molecular Hydrogen in Translucent Clouds
P117 Hutchings Hot Stars
P118 Linsky FUV Spectroscopic Survey of Cool Stars
P119 Vidal-Madjar Circumstellar Disks
P120 Feldman Solar System Objects
P123 Sonneborn Supernovae as Probes of Galactic Halos
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FUSE/Johns Hopkins Univ. Instrument and Operations Team Projects
P131 Friedman Small-Scale Structure in the ISM
P132 Kruk PG1159 Stars
P133 Bianchi Planetary Nebulae Central Stars
P134 Murphy Search for O VI Emission in the Halo of NGC4631
P135 Ake Epsilon Aurigae
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FUSE/U.C. Berkeley Instrument Team Projects
P151 Welsh Supernova Remnant Absorption Studies
P152 Welsh Herbig Be stars
P153 Griffiths Active Late-Type Stars
P154 Siegmund Flare Activity in Cataclysmic Variable Systems
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FUSE/Univ. of Colorado Instrument Team Projects
P163 Wilkinson T Tauri Stars
P164 Wilkinson Zeta Aur Systems
P166 J. Green X-ray Binaries
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FUSE Co-Investigator Projects
P179 Dupree Atmospheres of Cool Star Binaries
P180 Feldman Target of Opportunity Observations of Comets
P184 Hutchings Stellar Winds and CVs
P186 Linsky Transition Regions of PMS and Pleiades Age Stars
P187 Malina Pulsar and CV Observations
P191 Shull Lyman Break in Star-Forming Galaxies
P192 Siegmund T-Tauri Stars
P193 Snow Studies of IS and CS Gas and Dust
P198 Vidal-Madjar Blue Compact Galaxy and CSPN
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FUSE PI-Team Cycle 2 Programs
P211 Green Monitoring Variable Active Galactic Nuclei
P213 Sonneborn Circumstellar Interaction in SN 1987A
P214 Blair Balmer Supernova Remnants in the LMC
P215 Shull Two High-Extinction Stars in the LMC
P216 Snow Molecular Hydrogen in Translucent Clouds
P217 Fullerton Less Luminous Hot Stars in the LMC and SMC
P218 Dupree Cool Stars
P219 Vidal-Madjar Circumstellar Disks
P220 Feldman Solar System Objects
P221 Hutchings Far UV extinction curve in the SMC
P222 Iping The ISM near eta Carina
P223 Massa Phase-resolved spectroscopy of HD 5980
P224 Willis The Enigmatic WR Star HD 45166
P231 Andre O I Abundance and D/O
P232 Hoopes The HII Region N44C
P233 Catanzaro Magnetical chemically peculiar stars
P234 Sankrit Extended Grid in the Northeast Cygnus Loop
P235 Sonnentrucker H2, metals and DIBs in Reflection Nebulae
P241 Lehner FUSE Observations of the Magellanic Bridge
P242 De Marco Thermonuclear Runaways on Dwarf Novae
P243 Hoopes WR Star AV336a in the HeII Nebula N76-A
P247 Young 44i Bootis (HD 133640)
P248 Young The Symbiotic Star AG Draconis
P249 Andre HD in a Translucent Cloud
P250 Roberge Circumstellar Disk Target HD 141569
P251 Oliveira D/O ratio toward WD2247+583
P252 Pellerin Young Stellar Populations and the Starburst-AGN Connection
P263 Wilksinson Pre-Main Sequence Stars
P267 Green Extragalactic Hot Gas along the MRK1383 sightline
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FUSE PI-Team Cycle 3 Small Programs
P203 Sembach The Properties of Hot Gas in the Milky Way and
Magellanic Clouds (Magellanic Clouds)
P204 Sembach Deuterium Abundances and the D/H Ratio
(Local ISM)
P205 Sembach Deuterium Abundances and the D/H Ratio
(Galactic Disk)
P207 Sembach Deuterium Abundances and the D/H Ratio
(Snapshot Survey)
P209/P309 Sembach Deuterium Abundances and the D/H Ratio
(Solar System)
P323 Sembach Supernovae as Probes of Galactic Halos
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Abstract listings:
Major Program: The Properties of Hot Gas in the Milky Way and Magellanic Clouds
The FUSE PI and Science Team will study the physical properties and
distribution of hot gas in the interstellar media of the Milky Way and
Magellanic Clouds through comprehensive absorption line studies of the O VI
doublet and lower ionization lines in the FUSE bandpass. O VI is the best
diagnostic of hot (log T = 5-6) gas in the ultraviolet spectral region.
These observations will be covered under Team programs P101 (O VI Galactic
Halo), P102/122 (O VI Galactic Disk), and P103 (O VI Magellanic Clouds).
The Team D/H and O VI programs will share data. Note that the exposure
times given in this NRA listing for sight lines toward hot stars in P101,
P102/122, and P103 are appropriate for S/N ~ 30 at full resolution (0.03 A)
at 1032 A. Extragalactic sight line integrations in P101 will have S/N ~
12-30. D/H observations of some objects in the O VI program will be
several times longer than the listed integrations.
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Prog ID: P101
Title: The Properties of Hot Gas in the Milky Way and Magellanic Clouds (Galactic Halo)
Program_contact: Sembach
This portion of the O VI program will focus on understanding the character
of the O VI absorption in the Galactic halo along sight lines toward stars
and extragalactic continuum sources such as AGNs and QSOs. Regions to be
explored include the Galactic poles, the inner Galaxy, and the outer
regions of the Milky Way halo. The data obtained for this program will be
integrated with existing information from previous space missions to
provide a global picture of the hot gas content of the Milky Way halo. A
portion of the time for this program will be used to make measurements of
the O VI emission from the diffuse halo gas, though this is a secondary
objective since such measurements depend sensitively on instrument
performance.
There will be a large amount of auxiliary information obtained as part
of the O VI halo program. The Science Team will rely heavily upon these
data to undertake additional investigations of the chemical composition and
physical properties of the ISM, the properties of hot stars and their
winds, and the far-UV continua and absorption line properties of AGNs and
QSOs. Data from this program will also be used as a snapshot for
determining which extended sight lines are best suited for follow-up
studies of the D/H ratio. (See abstracts for programs P104, P105, P111,
P115, and P117 for additional details.)
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Prog ID: P102
Title: The Properties of Hot Gas in the Milky Way and Magellanic Clouds
(Galactic Disk)
Program_contact: Sembach
This portion of the O VI program will focus on understanding the character
of the O VI absorption in the Galactic disk at distances greater than ~ 1
kpc from the Sun. The survey will provide information for a statistical
study of the O VI absorption properties as well as detailed studies of
regions already known to contain hot gas through X-ray emission
measurements (e.g., SNRs, radio continuum loops).
Local interstellar medium data from the D/H program will be used to
understand the properties of the hot gas in the solar neighborhood. There
will be an additional "mini-survey" of several binary systems at multiple
epochs to search for the presence of broad shallow O VI absorption due to
very hot interstellar gas through a precise tomographic reconstruction of
the stellar absorption in the vicinity of the O VI lines. The Team will
also check for variability in the stellar O VI lines by observing several
objects with a range of spectral types several times during the mission.
There will be a large amount of auxiliary information obtained as part
of the O VI disk program. The Science Team will rely heavily upon these
data to undertake additional investigations of the chemical composition and
physical properties of the ISM and the properties of hot stars and their
winds. Data from this program will also be used as a snapshot for
determining which extended sight lines are best suited for follow-up
studies of the D/H ratio. (See abstracts for programs P104, P105, P115,
and P117 for additional details.)
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Prog ID: P122
Title: The Properties of Hot Gas in the Milky Way and Magellanic Clouds
(Galactic Disk)--continuation
Program_contact: Sembach
Program P122 is a continuation of program P102.
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Prog ID: P103/P203
Title: The Properties of Hot Gas in the Milky Way and Magellanic Clouds
(Magellanic Clouds)
Program_contact: Sembach
This portion of the O VI program will focus on understanding the character
of the O VI absorption in the Magellanic Clouds. Approximately 20 sight
lines will be investigated in the two galaxies. The sight lines will
include superbubble structures with strong X-ray emission and field
positions with little X-ray emission. The hot gas properties of the LMC
and SMC will be compared to those derived for the Milky Way.
There will be a large amount of auxiliary information obtained as part of the
O VI Magellanic Cloud program. The Science Team will rely heavily upon these
data to undertake additional investigations of the chemical composition and
physical properties of the ISM in the Milky Way and Magellanic Clouds, as well
as the properties of hot stars and their winds (See abstract for programs P115
and P117 for additional details.)
=====================================================================================
Major Program: Deuterium Abundances and the D/H Ratio
The FUSE PI and Science Team will determine the abundance of deuterium
and the D/H ratio in a variety of galactic environments through
comprehensive absorption line studies of the D I and H I Lyman series lines
in the FUSE bandpass. The sight lines studied will have varying degrees of
metallicity and different evolutionary histories. Various metallicity
markers (e.g., Oxygen, Iron) and ancillary ISM information (elemental
abundances, physical conditions, and gas kinematics) will be integral
components of all D/H analyses undertaken by the Team. The sky coverage of
these observations will be maximized to the greatest extent possible. The
D/H program encompasses Team programs P104 (D/H Local ISM), P105 (D/H
Galactic Disk), P106 (D/H Galactic Halo), P107 (D/H Snapshot Survey), P108
(D/H Extragalactic), and P109 (D/H Solar System).
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Prog ID: P104/P204
Title: Deuterium Abundances and the D/H Ratio (Local ISM)
Program_contact: Sembach
This portion of the D/H program will provide information for sight lines
confined to the local interstellar medium to determine the extent to which
the D/H ratio varies within a few hundred parsecs of the Sun. These
observations will significantly increase the amount of information
available for local deuterium abundance determinations and will enhance the
information for the local interstellar medium available from earlier
Copernicus satellite studies. Objects to be used as background sources
include cool stars, white dwarf stars, the central stars of planetary
nebulae, and a few A-type stars.
Auxiliary uses for the data will include general ISM studies and a survey
of hot gas within the Local Bubble. (See abstracts for programs P102/122 and
P115 for additional details.)
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Prog ID: P105/P205
Title: Deuterium Abundances and the D/H Ratio (Galactic Disk)
Program_contact: Sembach
This portion of the D/H program will provide information for sight lines
that extend beyond the local interstellar medium of the Galactic disk. The
sight lines covered will sample gas in spiral arm and interarm directions
several kiloparsecs from the Sun. Most of the objects observed will be
OB-type stars. Data from program P102/122 (O VI disk survey) will provide
an initial far-UV observation of a large number of sight lines. Many of
these sight lines will be re-observed for longer integration times (a
factor of 3-5x) as part of this program. All of the P102/P122 sight lines
should be considered potential candidates for this study.
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Prog ID: P106
Title: Deuterium Abundances and the D/H Ratio (Galactic Halo)
Program_contact: Sembach
This portion of the D/H program will provide information for sight lines
that extend into the Galactic halo. The directions to be studied include
sight lines toward stars at the Galactic poles as well as toward stars in
the inner and outer regions of the Galaxy. Most of the objects observed
will be OB-type stars. Data from program P101 (O VI halo survey) will
provide an initial far-UV observation of a large number of sight lines.
Many of these sight lines will be re-observed for longer integration times
(a factor of 3-5x) as part of this program. All of the P101 sight lines
should be considered potential candidates for this study.
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Prog ID: P107/P207
Title: Deuterium Abundances and the D/H Ratio (Snapshot Survey)
Program_contact: Sembach
This portion of the D/H program will provide short observations of many
AGNs and QSOs to check far ultraviolet flux levels and suitability of the
objects as background continuum sources for extended integrations. The
data produced from this snapshot survey will be used extensively as part of
program P111 to study the flux distribution and intrinsic absorption
properties of the AGNs and QSOs observed. (See abstract for program P111
for more information.) The Team will also use this data for studies of
extragalactic O VI and H I absorption at low redshift.
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Prog ID: P108
Title: Deuterium Abundances and the D/H Ratio (Extragalactic)
Program_contact: Sembach
This portion of the D/H program will provide extended observations of
extragalactic continuum sources for measurements of the D/H ratio in the
distant Galactic halo, high velocity clouds, and low redshift (z < 0.3)
absorption systems. These observations will provide unique opportunities
to measure the deuterium abundance in places that are difficult to observe
through absorption line studies of sight lines toward hot stars. Data from
this program will be used by program P111 for high quality measurements of
the far-UV continuum and absorption properties of AGNs and QSOs. (See
abstract for program P111 for more information.)
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Prog ID: P109
Title: Deuterium Abundances and the D/H Ratio (Solar System)
Program_contact: Sembach
This portion of the D/H program will focus on determining the D/H ratio
on Jupiter. The observation will consist of several planetary limb
pointings. The Jupiter D/H measurement will provide a reference value for
the ratio at the time the solar system was formed about 5 billion years
ago.
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Major Program: FUSE Studies of the Intergalactic Medium
Prog ID: P110/P210
Title: FUSE Studies of the Intergalactic Medium
Program_contact: Kriss
FUSE will provide an opportunity to explore absorption by He II in the
intergalactic medium (IGM) over the redshift range z=2-3. The planned
observations will measure the mean opacity of the IGM in coarse bins over
this redshift interval to study the patchiness of the IGM over different
lines of sight as a function of redshift. Deep observations of one or more
candidate QSOs will attempt to resolve the He II Ly alpha forest. These
observations will discriminate between discrete structures and distributed
gas as sources of the He II opacity. Detailed comparisons of the He II
forest lines and the H I Ly alpha forest lines will be used to determine
the ionization state of the absorbing structures and the shape of the
ionizing UV background spectrum.
=====================================================================================
FUSE Science Team Small and Medium Programs
Prog ID: P111
Title: Active Galactic Nuclei
Program_contact: Kriss
The nearest, brightest active galaxies have inspired our current vision
of the AGN paradigm. These same galaxies have been imaged with HST, have
the highest S/N HST and IUE far-UV spectra, and have the best X-ray
spectra. Prime goals for FUSE observations are the shape of the far-UV
continuum, the strength and velocity of the O VI emission line, strengths
of other far-UV lines such as C III 977 and N III 991, and the prevalence
of intrinsic absorption and Lyman limits. FUSE observations will resolve
velocity structure in the O VI absorbing gas, and in any neutral hydrogen
gas. Observations of Seyfert 2s (in addition to NGC 1068) will search for
strong line emission in O VI, C III, and N III indicative of shock-heated
gas. FUSE will also be sensitive to any molecular gas (visible as H_2
absorption) along the line of sight. In BAL QSOs, FUSE will be able to
measure the absorption in the EUV transitions of high ionization ions such
as Si XII. The detailed observations of selected objects in this program
will supplement the more general surveys of AGN being used to explore O VI
absorption and the D/H ratio in the galactic halo.
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Prog ID: P112
Title: O VI in Cooling Flow Clusters
PI: Oegerle
We will search for the O VI 1032/1038 emission lines produced in the warm
(300,000 K) intracluster gas in the cooling flow clusters A2597, A2199 and
A1795. The existence of this warm component of the ICM has never been
detected convincingly, although its presence is expected in the
conventional models of cooling flows. These 3 clusters have strong cooling
flows derived from their X-ray emission (>100 Msun/yr), as well as strong
H-alpha emission from cool (10,000 K) gas in their cluster cores.
Detection of the intermediate temperature gas at 300,000 K will provide a
strong link between these temperature regimes, and important information on
the thermal history of the gas in cooling flows.
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Prog ID: P113
Title: Circumstellar Interaction in SN 1987A
PI: PI: Sonneborn
FUV emission from SN 1987A in the Large Magellanic Cloud will be observed
to characterize the shock interaction between the high-velocity ejecta and
circumstellar gas. We will attempt to observe O VI emission and the full
blueward extent of the blue wing of Lyman-alpha, only part of which is
observable with STIS because of the high expansion velocity of the ejecta
(V>15,000 km/sec). Emission from recombination lines from the inner
circumstellar ring may also be present. The nearest companion star (Star
3) will also be observed.
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Prog ID: P114
Title: Supernova Remnants
PI: Blair
The FUSE Team Project on supernova remnants includes an absorption study
of the young Type 1a SN remnant SN1006 and studies of selected filamentary
emission regions in evolved galactic SNRs. Observations of the
"Schweizer-Middleditch" star behind SN1006 will be used to search for a
broad absorption from Fe III 1123, using FUSE's high dispersion to resolve
contaminating stellar photospheric lines from the broad line. The presence
of this line would indicate iron in the cool ejecta of the supernova.
Observations of key, well-studied SNR emission filaments will be used to
study different kinds of shock wave-ISM interactions, including
nonradiative and radiative shocks, and thermally unstable regions. FUSE
coverage of a range of ions and ionization stages at high spectral
resolution will provide a unique capability to diagnose the thermal,
chemical, and kinematic properties of these interactions. Observations of
an X-ray bright region will be used to search for faint, high-ionization
lines never observed previously in spectra of SNRs.
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Prog ID: P115
Title: Diffuse Molecular Hydrogen
PI: Shull
The FUSE PI team will study interstellar H_2 absorption spectra of
OB-stars in the Galactic halo, SMC, and LMC. The H_2 lines will be used to
derive molecular abundances, the CO/H_2 and HD/H_2 ratios, rotational
populations, rotational temperatures, gas densities, and UV radiation field
in diffuse clouds. We will measure the molecular abundances, including
CO/H_2 and HD/H_2, as a function of metallicity, and estimate the gas
pressure (nT) in the low halo. We will also observe H_2 in planetary
nebulae toward hot central stars.
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Prog ID: P116
Title: Molecuar Hydrogen in Translucent Clouds
PI: Snow
The FUSE PI team will observe 31 stars which lie behind translucent clouds
(i.e. clouds having total visual extinctions of around 2 magnitudes or
greater), in order to determine the H_2 column densities (for all stars on
the list) and the H_2 rotational excitations (for the brighter stars on the
list). The total H_2 column densities will be applied to studies of
gas-phase depletions and chemistry, while the rotational excitations will
be used to analyze the physical conditions (e.g. cloud densities,
temperatures, and radiation fields). In addition, the FUSE spectra will be
used to determine far-UV extinction curves for the program stars, and data
on lines of atoms and ions, as well as molecular transitions of species
other than H_2, will be used in a comprehensive analysis of cloud
abundances, depletions, and chemistry.
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Prog ID: P117
Title: Mass Loss and Stellar Winds of Hot Stars
PI: Hutchings
This program is intended to a) enable modelling of stellar winds
from FUSE spectra combined with HST/IUE range spectra, which will
yield proper determination of the wind ionization balance. The program
stars are selected mainly from the LMC and SMC and will be combined
with the Galactic star sample from other programs, to b) enable a
comparison of winds in stars with matched spectral type and luminosity
in the 3 different environments, since abundance is known to be an
important parameter in driving winds. Spectral types range through WR,
and O3 to B2. Exposures are designed to provide a minimum S/N of 30
over 0.2 Angstroms; in many cases this is exceeded.
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Prog ID: P118
Title: Spectroscopic Survey of Cool Stars
PI: Linsky
This program will obtain far-UV spectra of cool stars that span a broad
range of spectral type and luminosity class. It is our intention to obtain
these spectra early in the FUSE program and to provide the spectra quickly
to the user community in order to guide potential guest investigators in
designing their observing programs. The specific science objectives
include: (1) studying transition region dynamics (winds and downflows), (2)
modeling the thermal structure of transition regions, (3) measuring
electron densities, (4) search for low temperature coronae, (5) studying
molecular excitation and fluorescence processes, and (6) inferring how the
transition regions of spectroscopic binary systems differ from those of
single stars.
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Prog ID: P119
Title: Circumstellar Disks Around Main-Sequence and Pre-Main-Sequence Stars
PI: Vidal-Madjar
The purpose of this program is to provide new insight on the signatures
of circumstellar gas around main-sequence and pre-main-sequence stars. For
some stars, the already detected gas may be the by-product of some activity
(like evaporation and/or collision of kilometer-sized bodies) in a young
planetary system in its clearing out phase. Spectroscopic variations
observed around the targets stars (PMS, Herbig AeBe) present strong
similarities with the already observed ones, but the origin of the
circumstellar gas within these systems is still unclear. Detection of
deuterium may help in identifying the origin of the gas. These
observations are expected to allow the identification of the main form of
the gaseous phase (H_2, CO, OI, NI, CII ?) and provide information on the
ionization equilibrium of the zero radial velocity as well as of the
accreting gas. Analysis of multiplet ratios will allow to probe the sizes
of the inflowing gas structures. Also, in order to better understand the
evolution of circumstellar gas from young stellar objects to main sequence
stars, a few very young B-type stars are included as being members of a
binary system with a T-Tauri companion.
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Prog ID: P120
Title: FUSE Solar System Studies
PI: Feldman
H_2 emissions from both Jovian auroral regions measured with the
high-throughput aperture (MDRS) will determine temperatures and
self-absorption. Atomic H emissions from the bulge region measured by the
high resolution aperture (HIRS) will determine the dynamics of the bulge
and anti-bulge regions. The high-throughput aperture will be used to
search for HD fluorescently pumped by solar Lyman-beta as well as to
determine if there is a correlation of the H_2 Lyman and Werner bands with
Lyman-alpha in the bulge region. The excitation of H_2 in the atmosphere
of Saturn will be similarly studied. Io Torus emissions will be measured
using the high-throughput aperture (MDRS) to determine ion velocity
profiles and with the large science aperture to search for minor
constituents. Observations of Venus will address the question of the
atmospheric D/H ratio.
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Prog ID: P123
Title: Supernovae as Probes of Galactic Halos
PI: Sonneborn
FUSE observations of a newly discovered, bright (V<14) core-collapse supernova
(Types II or Ib) will be used to study interstellar properties of the sightline.
The full range of interstellar species present in the FUSE wavelength range will
be utilized to examine kinematics, depletions, and abundances of foreground gas,
the Milky Way halo, the ISM of the supernova's host galaxy, and the intergalactic
medium. Any data obtained from this program will be made available to other FUSE
programs to study the properties of the supernova outburst.
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FUSE/Johns Hopkins Univ. Instrument and Operations Team Projects
Prog ID: P131
Title: Small-Scale Structure in the ISM
PI: Friedman
The properties of the interstellar medium on scale sizes of about 1 pc are
not well understood. Even as fundamental a parameter as the range of cloud
sizes has not been measured properly. Some data suggest only weak opacity
variations on scales of ~1 pc, and essentially none below 0.2 pc. Other
data, especially in the UV and radio, suggest absorption line equivalent
width variations as great as 25-50% toward targets with separations smaller
than 3000 AU (~0.01 pc) at a distance of ~200 pc. The goal of this program
is to observe closely spaced lines of sight toward spatially adjacent
targets in an open cluster (NGC2264, distance=750 pc) in order to measure
or place limits on various properties of clouds in the local interstellar
medium. Among these properties are the sizes of the clouds and possible
anomalous abundances. In addition, these observations may provide measures
of metallicity and depletion gradients across the face of the cluster.
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Prog ID: P132
Title: PG1159 Stars
PI: Kruk
The hot metal-rich hydrogen-deficient white dwarfs known as PG1159 stars
provide a unique probe of the late stages of stellar evolution. Present
theories of stellar evolution do not yet produce stars that match the
properties of PG1159 stars. FUSE observations will provide improved data
on the surface compositions of these stars; in addition, the O VI resonance
line profiles will be searched for evidence of ongoing mass-loss. The long
exposure on WD2117+341 is used to search for the effects of the pulsations
on certain diagnostic line profiles. The 2000s exposure on HS2324 is a
snapshot: if the spectrum shows sufficient flux then some time will be
reallocated within the program.
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Prog ID: P133
Title: Planetary Nebulae Central Stars
PI: Bianchi
Central stars of Planetary Nebulae (CSPN) are among the hottest stars in
the H-R diagram. IUE and HST observations show that CSPN have significant
supersonic winds and mass loss. Accurate measurements of the wind velocity
and mass loss rate in CSPN are a crucial to test of whether current
theories of radiation pressure accelerated winds apply to evolved, high
gravity stars, and to understand the formation and evolution of the nebular
shell, since the photons from the hot central star, and the momentum of its
supersonic wind are responsible for the ionization of the visible nebula,
and influence the dynamics of the expanding shell. IUE and HST data give
only partial information about mass loss, since they can only observe the
(often saturated) resonance lines of CIV, SiIV and NV. FUSE can observe
wind lines in a greater spread of species and ionization states, especially
the hot O VI 1032,1037 doublet, from which the wind ionization can be
determined accurately. UV (IUE/HST) and optical spectra are already
available for a consistent analysis of photospheric and wind lines. The
line profiles will be analyzed with different methods (SEI, SSBAL, EMISSEI)
to derive wind velocity, mass loss rate, gravity, temperature and
luminosity. Moreover, measurements of the stellar continuum in the FUSE
range will yield better determinations of temperature and luminosity, both
because of the hot temperatures of the stars, and because nebular continuum
emission contaminates the flux of CSPN longwards of about 1400 Angstroms,
but drops drastically below 1300 Angstroms. Therefore, FUSE spectra of
CSPN can help our understanding of mass loss mechanisms, PN formation and
evolution (physical interpretation of the morphology), nebular ionization,
and post-AGB evolution.
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Prog ID: P134
Title: Search for O VI Emission in the Halo of NGC 4631
PI: Murphy
We propose to look for the O VI 1032/1038 emission lines from hot gas in
the disk and halo of the edge-on spiral galaxy NGC 4631. ROSAT
observations of NGC 4631 clearly show a concentration of soft X-ray
emission north of the galaxy's plane directly above an area of high star
formation activity. The X-ray spectrum implies the presence of a soft
X-ray gas component at a temperature of less than 1 million degrees. Since
O VI is the best diagnostic of gas at this temperature in the FUSE
bandpass, our measurements of the O VI emission strength will help us to
understand the physical state, total content, and scale height of hot gas
in the halo of NGC 4631. These quantities can then be directly compared to
values derived for the Milky Way through the O VI Program.
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Prog ID: P135
Title: Epsilon Aurigae
PI: Ake
FUSE will be used to study the nature of the unusual eclipsing
spectroscopic binary, epsilon Aurigae. The most favored model of this
system is that the secondary object is a large, cold disk seen nearly
edge-on. IUE and GHRS observations indicate the existence of a far-UV
excess compared to other A-F type supergiants, presumably from a hot star
in the center of the disk. The main difficulty in interpreting the UV data
is that the primary star still contributes significant flux down to
1400-1500 Angstroms. FUSE observations will perform a more direct
examination of the secondary, free from contamination by from the
photosphere of the primary star. Measurements will be made to determine
the physical parameters of the central star, and study variability and gas
motions in the disk.
=====================================================================================
FUSE/U.C. Berkeley Instrument Team Projects
Prog ID: P151
Title: Supernova Remnant Absorption Studies
PI: Welsh
We will observe 4 early-type stars in the line-of-sight towards the
Monoceros Loop supernova remnant in order to investigate the dynamics,
ionization state and elemental abundances of the disturbed, absorbing
interstellar gas associated with the remnant.
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Prog ID: P152
Title: Herbig Be stars
PI: Welsh
We will repeatedly observe 4 early-type Herbig Be stars which are thought
to possess gaseous circumstellar disks. Our investigation will focus on
the strong stellar FUV line profiles to determine the extent of time
variability due to mass loss and accretion processes. We will also analyze
the physical state of the molecular absorption lines sampled in the
interstellar gas serendipitously observed in the line-of-sight to these
objects.
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Prog ID: P153
Title: Active Late-Type Stars
PI: Griffiths
We will complete repeated exposures of the active late-type RS CVn stars
AR Lac and HR 1099, and perform an extended exposure of the G8V star Xi Boo A.
We will obtain a better description of the transition regions of these
stars by completing the full emission measure distribution and accurately
measuring the plasma electron density. We hope to gain a detailed
understanding of the connection between magnetic activity at the
photospheric and transition region levels, and will search for solar-like
coronal mass streamers using O VI (1032,1038 Angstrom) line profiles.
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Prog ID: P154
Title: Flare Activity in Cataclysmic Variable Systems
PI: Siegmund
We will repeatedly observe one pre-CV and one normal CV eclipsing binary
system to monitor the level of FUV flare activity that is routinely
observed in these systems in other wavelength bands. We will observe the
FUV emission from the surrounding gas disk and wind, the white dwarf
companion, and a possible hot disk corona produced by EUV/X-ray radiation
from the white dwarf that photoionizes and heats the disk surface.
=====================================================================================
FUSE/Univ. of Colorado Instrument Team Projects
Prog ID: P163
Title: T-Tauri Stars
PI: Wilkinson
FUV spectra of pre-main sequence (PMS) stars show high temperature emission
lines from magnetically heated regions and excited molecular lines from the
circumstellar environment. The FUSE region is still largely unexplored for
PMS stars and contains unique diagnostics such as the O VI doublet, H Lyman
lines, and the H_2 Lyman bands. Our targets are the Classical T Tauri star
T Tau and the Herbig Ae star HD104237. T Tau shows a rich UV spectrum of a
wide range of ionic and H_2 lines, while the UV spectrum of HD104237 shows
wind-dominated emission lines below 1500 A.
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Prog ID: P164
Title: Zeta Aurigae Systems
PI: Wilkinson
Zeta Aurigae/VV Cep eclipsing binary systems offer the most detailed
method of studying mass loss from cool supergiant stars. The FUV continuum
from the hot main-sequence secondary star provides a probe through the
outer atmosphere and wind of the evolved primary star. The absorption
spectra obtained will allow detailed investigation of the flow properties
and ionization structure of these binaries, leading to improved mass-loss
rates and wind energy budgets.
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Prog ID: P166
Title: X-ray Binaries
PI: J. Green
Observations of bright X-ray binaries will be used to determine the
physical conditions in the companion star's wind and the effects of the
high energy spectrum on the wind environment.
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FUSE Co-Investigator Projects
Prog ID: P179
Title: Atmospheres of Cool Star Binaries
PI: Dupree
The densities, mass motions, and emission measures will be evaluated for
a selection of single stars and binary systems containing cool stars with
various rotation periods to assess the effects of rotation upon the
structure and energy balance of a stellar atmosphere. Most systems will be
observed 3 times.
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Prog ID: P180
Title: Target of Opportunity Observations of Comets
PI: Feldman
FUSE will attempt to determine the argon/oxygen ratio in a
target of opportunity comet whose activity level and orbit are suitable for
the observation. In addition, we will search for molecular hydrogen
released directly by the cometary nucleus and for neutral and singly
ionized nitrogen. These measurements will be normalized to a water
production rate derived from the observed hydrogen Lyman series.
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Prog ID: P184
Title: Stellar Winds and CVs
PI: Hutchings
Three stars in M33/M31 will be observed to study their stellar winds.
The disk-dominated supersoft binary X-ray source 0513-69 in the LMC will be
observed. Three CV binaries will be observed, with readouts at intervals
which will sample their orbital and other variations. These targets are
highly variable - maximum visible magnitude is given.
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Prog ID: P186
Title: Transition Regions of PMS and Pleiades-Age Stars
PI: Linsky
The objectives of this program are to study the dynamics, thermal
structure, and energy balance in the transition regions of young stars,
including pre-main sequence and Pleiades age stars. The observations will
address these questions by measuring the far-UV fluxes, line widths, and
Doppler shifts of the O VI and other far-UV transition region lines. We
will be studying some young A-type stars to determine whether their
transition regions differ from those of cooler stars, and will analyze any
flares observed in these young stars and a reference late-M star.
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Prog ID: P187
Title: Pulsar and CV Observations
PI: Malina
PSR_0656+14: Measurement of surface thermal emission from neutron
stars (NS) is essential to theories regarding the condensed matter state
equation, the thermal evolution of NS, and of NS atmospheres. We propose
to conduct 50 Ang band FUV photometric observations of PSR B0656+14, an
X-ray, SXR and EUV bright isolated NS with an optical counterpart. FUV
photometry will provide critical characterization of the NS's surface
thermal radiation. Higher energy observations may be effected by poorly
established effects including magnetized atmospheres, chemical
compositions, temperature gradients and gravitational effects. Optical
observations may be subject to non-thermal effects.
V3885 Sgr: V3885 Sgr is one of the brightest nonmagnetic cataclysmic
variables. We propose to observe V3885 Sgr for 5 to 6 contiguous FUSE
orbits, achieving a S/N of about 12 at full resolution even at the troughs
of the source's O VI absorption lines in each spectrum (assuming 2000 sec
visibility per orbit). The primary purpose of the observations is to use
the source as a bright continuum against which to study local interstellar
absorption lines. Although observed on Malina's Co-I Program, the data
will be analyzed in collaboration with members of the O VI Project.
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Prog ID: P191
Title: Lyman Break in Star-forming Galaxies
PI: Shull
We will observe a blue, metal-poor, star-forming galaxy, Mrk 357 (z =
0.053) shortward of its (rest-frame) Lyman limit to measure or set limits
on the Lyman continuum escape fraction. This fraction constrains the HI
opacity and topology of gas layers in the parent galaxy and its halo, and
it gauges the potential contribution of starbursts to the metagalactic
(IGM) radiation field. A related goal is to use the spectrum longward of
the Lyman limit for better understanding the star, dust and gas content of
the galaxy.
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Prog ID: P192
Title: T Tauri Stars
PI: Siegmund
We shall observe two relatively unobscured T Tauri stars to investigate the
emission from accreting hot gas known to be present in these systems from
previous IUE data. Observations of these emission processes will help in
understanding the role of circumstellar disk gas in these pre-main sequence
systems.
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Prog ID: P193
Title: Studies of Interstellar and Circumstellar Gas and Dust
PI: Snow
Studies under this program fall into three distinct categories:
(1) a detailed analysis, with enhanced S/N, of the spectra of two stars (HD
24534 = X Persei; and HD 23180 = o Per) for interstellar lines, with
emphasis on weak molecular features and lines below 1000 Angstroms; (2) a
study of absorption and emission in the spectra of three planetary nebula
central stars; and (3) a search for UV diffuse bands as stationary features
in the spectra of high- amplitude spectroscopic binaries.
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Prog ID: P198
Title: Blue Compact Galaxy and CSPN
PI: Vidal-Madjar
IZW18 is known to be a blue compact galaxy presenting a very low
metallicity. The purpose of this investigation is to search for H_2 in the
context of such a low metallicity, probably dust free object. A high
velocity cloud is also present along this line of sight. These
observations will allow the precise evaluation of a much longer exposure to
further study both the galaxy and the intervening high velocity
cloud.
Several programs can also be done simultaneously by observing the central
stars of some bright Planetary Nebulae (PN):
(a) The wavelength range is particularly appropriate to study the continuum,
the temperature and the wind of the PNe central stars;
(b) In addition to the stellar continuum, the spectra will yield information
concerning the nebula;
(c) FUSE will offer the possibility to detect molecular hydrogen
lines in absorption against the stellar continuum. It should
then be possible to determine how much additional H_2 is formed by
shocks in the stellar winds.
(d) Finally, the non-detection of deuterium should allow a direct check of its
evolution within stars since these PN were selected for their different 3He
environment.
=====================================================================================
FUSE PI Team Major Programs for Cycles 2 and 3
Prog ID: P203
Title: The Properties of Hot Gas in the Milky Way and Magellanic Clouds
(Magellanic Clouds)
Program_contact: Sembach
This portion of the O VI program will focus on understanding the character
of the O VI absorption in the Magellanic Clouds. Approximately 20 sight
lines will be investigated in the two galaxies. The sight lines will
include superbubble structures with strong X-ray emission and field
positions with little X-ray emission. The hot gas properties of the LMC
and SMC will be compared to those derived for the Milky Way.
There will be a large amount of auxiliary information obtained as part of the
O VI Magellanic Cloud program. The Science Team will rely heavily upon these
data to undertake additional investigations of the chemical composition and
physical properties of the ISM in the Milky Way and Magellanic Clouds, as well
as the properties of hot stars and their winds.
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Prog ID: P204
Title: Deuterium Abundances and the D/H Ratio (Local ISM)
Program_contact: Sembach
This portion of the D/H program will provide information for sight lines
confined to the local interstellar medium to determine the extent to which
the D/H ratio varies within a few hundred parsecs of the Sun. These
observations will significantly increase the amount of information
available for local deuterium abundance determinations and will enhance the
information for the local interstellar medium available from earlier
Copernicus satellite studies. Objects to be used as background sources
include cool stars, white dwarf stars, the central stars of planetary
nebulae, and a few A-type stars.
Auxiliary uses for the data will include general ISM studies and a survey
of hot gas within the Local Bubble. (See abstracts for programs P102/122 and
P115/P215 for additional details.)
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Prog ID: P205
Title: Deuterium Abundances and the D/H Ratio (Galactic Disk)
Program_contact: Sembach
This portion of the D/H program will provide information for sight lines
that extend beyond the local interstellar medium of the Galactic disk. The
sight lines covered will sample gas in spiral arm and interarm directions
several kiloparsecs from the Sun. Most of the objects observed will be
OB-type stars. Data from program P102/122 (O VI disk survey) will provide
an initial far-UV observation of a large number of sight lines. Many of
these sight lines will be re-observed for longer integration times (a
factor of 3-5x) as part of this program. All of the P102/P122 sight lines
should be considered potential candidates for this study.
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Prog ID: P207
Title: Deuterium Abundances and the D/H Ratio (Snapshot Survey)
Program_contact: Sembach
This portion of the D/H program will provide short observations of many
AGNs and QSOs to check far ultraviolet flux levels and suitability of the
objects as background continuum sources for extended integrations. The
data produced from this snapshot survey will be used extensively as part of
program P111 to study the flux distribution and intrinsic absorption
properties of the AGNs and QSOs observed. (See abstract for program P111
for more information.) The Team will also use this data for studies of
extragalactic O VI and H I absorption at low redshift.
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Prog ID: P209/P309
Title: Deuterium Abundances and the D/H Ratio (Solar System)
Program_contact: Sembach
This portion of the D/H program will focus on determining the D/H ratio
on Jupiter which will provide a reference value for the ratio at the
time the solar system was formed about 4.5 billion years ago. The
observation will consist of several planetary limb drift scans. In
this mode, the center of the MDRS or HIRS will move, perpendicular to
the long dimension of the slit, from 0.80 R_j to 1.2 R_j along a jovian
radius during a single orbit, and this scan will be repeated for 5
contiguous orbits during a single visit. The data will be obtained in
time-tagged mode allowing separate extractions of the disk and limb
spectra. The disk spectrum will show electron excited dayglow spectra
of H_2 and HD and permit a determination of the vibrational temperature
of the H_2, needed for modeling of observed HD and D Lyman-beta
emission which should be enhanced at the limb. The contiguous orbits
will make it possible to take into account any effects of the
equatorial hydrogen bulge which is centered on 90 degrees in System III
longitude.
=====================================================================================
FUSE PI Team Cycle 2 Programs
Prog ID: P211
PI: Green, Richard
Institution: NOAO
Title: Monitoring Variable Active Galactic Nuclei
We will monitor the highly variable O VI emission and associated absorption
in three bright Seyfert galaxies. The screening observations for good AGN
sightlines are, of course, taken at arbitrary times with respect to AGN light
curves. In several cases of well-known Seyfert galaxies, FUSE caught them in a
low state. To our surprise, the typical broad emission line expected for O VI
had nearly vanished, leaving a narrower line component that was essentially
invisible when observed in a high state by HUT. The emission velocity widths
fall in the range of 400-800 km/s. Two different scenarios may explain the
observations, and both may be operative to some degree. There may be an
extended narrow-line region in O VI. When the broad line region fades as
ionizing flux drops, the narrow-line component remains more nearly constant
but gains prominence in the observed spectrum. Alternatively, there may be
bi-conical outflow as in NGC 4151. As the accretion state changes, the
structure of this focused wind changes both in ionization and density. The
velocity spread and strength of O VI depends on the physical details of where
in the flow the line is produced. An additional diagnostic is provided by the
associated absorption. The degree to which it covers the broad line, narrow
line, and continuum places the absorbing gas geometrically and constrains the
location of the emission-line gas. The extent to which the strength of
absorption varies with the continuum and emission components gives further
information about its location in the nuclear region.
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Prog ID: P213
Title: Circumstellar Interaction in SN 1987A
PI: Sonneborn
FUV emission from SN 1987A in the Large Magellanic Cloud will be observed
to characterize the shock interaction between the high-velocity ejecta and
circumstellar gas. We will study observe O VI emission and the full
blueward extent of the blue wing of Lyman-alpha, only part of which is
observable with STIS because of the high expansion velocity of the ejecta.
Emission from recombination lines from the inner circumstellar ring may also be
present. The nearest companion stars (Star 2 and 3) will also be observed.
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Prog ID: P214
PI: Blair, William P.
Institution: Johns Hopkins University
Title: FUSE Observations of Balmer Supernova Remnants in the LMC
We propose to observe the four Balmer-dominated (Type Ia) SNRs in the Large
Magellanic Cloud. These objects will all be observed with Chandra, so FUSE
observations will provide information on OVI line intensities for comparison
with OVII and OVIII from the soft X-ray region. The combined data will
provide strong constraints on the dominant emission mechanism operating in
young SNRs arising from Type Ia supernovae. The LMC set of objects is unique
in permitting reasonable estimates of the total OVI emission from each object
with relatively little foreground extinction.
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Prog ID: P215
PI: Shull, Michael
Institution: University of Colorado
Title: Two High-Extinction Stars in the LMC
The fundamental physical and chemical processes at work in molecular
clouds are key objects of FUSE science. Preliminary results on H2 in
the LMC, based on available PI Team data, suggest a reduced molecular
fraction in the low-metallicity LMC gas. Although this result provides
the first direct evidence of a metallicity dependence in the formation
rate of interstellar H2, the available FUSE targets do not sample the
high-extinction regime where the correlation between E(B--V) and molecular
fraction is strong. Therefore, we cannot test whether the apparent
reduction in molecular fraction is due to reduced formation rates, high
radiative destruction rates, or selection effects. We propose observations
of 7 LMC stars and 2 SMC stars with E(B--V) = 0.20 -- 0.42, which will
allow us to test cloud models that incorporate different assumptions about
the formation rate of H2 as a function of metallicity. We will also
obtain CO emission maps in these selected regions to assess the CO/H2
ratio in this gas. As a key goal of FUSE H2 science, this test
can be applied only to sight lines for which the variation of molecular
fraction with extinction can be tightly controlled.
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Prog ID: P216
PI: Snow, Theodore P.
Institution: University of Colorado
Title: FUSE Team Project on Molecular Hydrogen in Translucent Clouds
This Cycle 2 program plans observations of 11 stars (in addition to
the original list) as an add-on to our medium project to study molecular
hydrogen in translucent clouds. The new stars have been selected
on the basis of reddening, known extinction and interstellar line
parameters, and inclusion in the comprehensive survey of diffuse
interstellar bands being carried out by group member Don York and
collaborators (e.g. Snow, Welty et al.).
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Prog ID: P217
PI: Fullerton, Alex
Institution: University of Victoria
Title: Less Luminous Hot Stars in the LMC and SMC
The primary goal of the FUSE P117 Hot Star program is to characterize
the stellar winds of a representative sample of early-type stars in
the Galaxy, Large Magellanic Cloud (LMC), and Small Magellanic Cloud (SMC),
in order to study the properties of mass-loss via stellar winds as a function
of metallicity. Information about the ionization balance, velocity law,
and mass-loss rates associated with these winds can be derived from modeling.
However, in order to understand the behavioral trends of these properties,
good coverage of the relevant temperature and luminosity classes is required.
Through P117 and other PI-team programs, this spectral domain is well covered
for Galactic OB and WR stars. However, the existing coverage of parameter
space for the LMC and SMC is biased toward supergiants and hotter stars.
With this proposal, we seek to mitigate these biases by supplementing
the original sample of PI and GI targets in the LMC and SMC with
objects of lower luminosity. This additional coverage of the H-R diagram
will enable us to determine where the stellar wind turns off, and the
dependence of this point on metallicity. Objects in the SMC are particularly
interesting, since their abundances reflect the metallicities - and hence the
behavior of stellar winds - in the early universe.
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Prog ID: P218
PI: Dupree, Andrea
Institution: Harvard-Smithsonian Center for Astrophysics
Title: Cool stars
This program will obtain far-UV spectra of cool stars that span a
broad range of spectral type and luminosity class. The specific
science objectives include: (1) studying transition region dynamics
(winds and downflows), (2) modeling the thermal structure of
transition regions, (3) measuring electron densities, (4) search for
low temperature coronae, (5) studying molecular excitation and
fluorescence processes, and (6) inferring how the transition regions
of spectroscopic binary systems differ from those of single stars.
All five targets have been previously observed with FUSE, and their
spectra assessed. They indicate that FUSE will identify the source of
the stellar coronal holes and define the acceleration and transition
region densities over the cool half of the HR diagram. However,
further observations are required to improve the quality of the line
profiles from which conclusions can be drawn. In particular we require
observations during orbial night-time to remove any uncertainties due
to solar and airglow contamination.
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Prog ID: P219
PI: Vidal-Madjar, Alfred
Institution: Institut d'Astrophysique de Paris
Title: Circumstellar Disks Extension Program
The purpose of this program is to obtain new spectra of the most
important targets of the Circumstellar disk program (P119, Q119, Q219)
which aims to observe the signatures of circumstellar gas around
main-sequence and pre-main-sequence stars.
The objective of this program is to monitor the spectroscopic
variabilities of the targets for which FUSE spectra have already been
obtained or will be obtained in the coming months.
The selected targets have already shown signature of spectroscopic
variations in the UV or the visible. Although these variations are often
interpreted in terms of proto-planetary activity, a clear understanding
is still to be established. Further observations and studies are thus
needed.
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Prog ID: P220
PI: Feldman, Paul D.
Institution: The Johns Hopkins University
Title: FUSE Team Project on Solar System Objects
The original P120 proposal requested observations of Jovian aurora with
the MDRS and the Io plasma torus with both LWRS and MDRS apertures.
Because of anticipated difficulties in achieving pointing at specific
regions of the torus or polar aurora and problems in maintaining
co-alignment of the four channels, the initial observations of these
targets were made with the LWRS. However, there remains a strong
desire to observe both targets at the higher spectral resolution
afforded by the MDRS aperture. For example, one of the initial
objectives for the Io torus was to determine the velocity distribution
(expected to be non-Maxwellian) of the principal sulfur ions, S II, S III
and S IV. Higher resolution would also make the analysis of the
multitudinous lines of H_2 seen in the auroral spectrum much more
tractable. We propose to use the MDRS in a short raster scan for both
targets. This will alleviate the pointing and co-alignment problems
cited above and additionally will provide, in the case of the Io torus,
information about the radial distribution of electron temperature and
density, relative ion abundances and ion temperature, with which to
test current models.
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Prog ID: P221
PI: Hutchings, John
Institution: HIA, NRC of Canada
Title: Far UV extinction curve in the SMC
The observation is of reddened stars in the SMC
which will yield an far UV extinction curve for this galaxy.
UV extinction in galaxies of low metal abundance are of high interest
in current cosmology research as well as in understanding the
evolution of our neighbour galaxy. The early universe is seen at rest
UV wavelengths because of redshifting, but the energy budget and
completeness will not be known until proper allowance is made for
extinction. It is known that the SMC UV extinction curve is steeper and
different in shape from that seen in the more evolved environment of
our Galaxy. The extension of this to the Lyman limit is not known and
of high importance as it rises with decreasing wavelength.
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Prog ID: P222
PI: Iping, Rosina
Institution: CUA, NASAGSFCLASP
Title: FUSE OBSERVATIONS IN SUPPORT OF ETA CARINAE
Eta Carinae, located in the association Trumpler 16 in the Carina Nebula (NGC
3372), was observed by FUSE in February and March 2000 and was found to have
surprisingly bright far uv fluxes and strong H2 absorption. If circumstellar nature
of H2 can be established, this would be the first detection of molecules in the eta Car
nebulosity. Do the large FUV fluxes provide evidence for or against a binary
companion of eta Car or constrain the mass of this object? In an effort to
clearly distinguish between the interstellar and circumstellar material,
three OB stars close (within 1 arcmin) to Eta Carinae, Trumpler 16 will be observed.
Additional lines of sight close to eta Car should help to better understand the
ISM near eta Car. To complement the observation of eta Carinae, three other luminous
blue variables, P Cygni, AG Carinae and HR Carinae will be observed. Comparison of
additional LBVs with eta Car will help to establish in what way
they are similar and/or different. P Cygni is especially important because
it is widely regarded as an eta Car analog in terms of its UV properties
(Ebbets et al. 1997, ApJ, 489, L161). These observations will give us a better
understanding what LBV's look like in the FUV.
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Prog ID: P223
PI: Massa, Derck
Institution: Raytheon STX
Title: Phase-Resolved FUV Spectroscopy of the Binary HD 5980
HD 5980 is the brightest star in the SMC and indicative of the luminous
objects which dominate the light from distant, metal poor, young galaxies
(Koenigsberger et al., 2000, ApJ, 542, 428). HD 5980 is also an eclipsing
WN+O binary with an eccentric orbit and a period of 19.26 days (Breysacher
& Perrier 1980, A&A, 90, 207). In addition, in 1994 one component of the
system underwent a Luminous Blue Variable (LBV) outburst of the sort
experienced by the most luminous stars in the universe (Moffat et al.
1998, ApJ, 497, 896). The binary nature of HD 5980 is fortuitous, since
it allows us to determine far more about the object than we could ever
glean from a single star. Because the two components have different
temperatures, observations of the eclipses at different wavelengths reveal
different aspects of the stars.
To probe the massive winds of the binary, to attempt to disentangle the
contributions of the two components and to make unambiguous
identifications of the ISM lines along the line of sight, better phase
coverage of the orbit is essential. Three
observations near each of the two eclipses (phases 0.00 and 0.36) and one
near each opposition (phases 0.13 and 0.78), where the line of sight to
the system does not intersect the interacting winds.
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Prog ID: P224
PI: Willis, Allan
Institution: University College London
Title: The Enigmatic WR Star HD 45166
It is proposed to secure FUV spectra of the qWR star HD45166.
These data will provide measurents of qWR emission lines in important
species like CIII, CIV, SIV, SVI, OVI, NIII. Their analysis using state of
the art, nLTE model atmosphere techniques will determine the fundamental
properties of the low mass, qWR star, and fix its evolutionary status.
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Prog ID: P231
PI: Andre, Martial
Institution: John Hopkins University
Title: OI Abundance and D/O
The Oxygen abundance is a critical point for D/H measurements with
FUSE since D/O can be determined with greater accuracy. Using the
Copernicus data, astronomers found a depletion of Oxygen in the gaz
phase (com
pared to solar abundance) and started to investigate
the O/H(total) ratio in the LISM. From Deboer et al (1981) to Keenan
et al(1985), the determination of this ratio proved to be difficult
and nothing could been said about possible variations because of the
scatter of data and the error bars.
Then, using GHRS data, Meyer at al (1998) tried to set a Definitive
Oxygen Abundance and found 50 % depletion in the LISM (gaz phase).
Still, the survey implied only 13 targets so that nothing can be said
as to variation or gradient. In particular, distant targets are required
to test the metal poor infall scenario (to explain the LISM depletion)
but such targets show strong H2. The next step would be to improve the
statistic but to do so means to be able to choose a large sample
of targets for which a non negligible fraction of H may be in H2
molecules.
The most useful sample of targets comes from the Lauroesch survey (STIS
1998) where lines of sight were selected to show 1356 A OI transition.
From this survey, I extracted 19 very nice lines of sight, showing
clear velocity structure and no blending. Actually, 14 of them are
planned FUSE target or already in the FUSE archive. Among the 5 other
targets, 3 have a E(B-V) greater than .2 and FUSE is the only instrument
able to give their H2 column density.
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Prog ID: P232
PI: Hoopes, Charles G.
Institution: Johns Hopkins University
Title: The HII Region N44C
I am proposing to observe the central star of the HII region N44C in
the LMC, as well as the surrounding ionized gas. This HII region
contains HeII emission, but the central star has been classified as
type O7, not hot enough to produce the 54 eV photons necessary to
ionize HeII. With a FUSE spectrum we can search for other highly
ionized elements requiring photon energies similar to that of
HeIII. The recombination time of these elements can constrain and
perhaps eliminate the hypothesis that the ionization source has turned
off. We can also determine the metallicity in the region to see
whether enrichment by an evolved companion has occurred, and use the
stellar spectrum to refine the spectral classification.
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Prog ID: P233
PI: Catanzaro, Giovanni
Institution: Johns Hopkins University
Title: Vertical abundance stratification in the atmospheres of Chemically
Peculiar stars
Magnetic Chemically Peculiar (CP) stars are characterised by spectral,
photometric and magnetic variations with a common period. In the oblique
rotator model, proposed by Stibbs (1950), chemical elements are not
homogeneusly distribuited on the stellar surface, and the observed variations
are due to the stellar rotation.
The anomalous abundances are caused by diffusion process (Michaud, 1970).
Magnetic fields are suspected to influence the diffusion by suppressing
mass-motions and changing the path of ionised species (Michaud et al., 1981),
so that diffusion in CP stars results in a non-homogeneous distribution of
elements over the stellar surface.
The vertical stratification of chemical elements in the atmospheres of CP stars
was predicted from results of radiative diffusion processes. In order to study
this phenomenon, one attempt we can make is to compute chemical abundances by
measuring different lines of the same element, formed at different layers of
the atmosphere.
FUSE offers the possibility to look very deep in the atmosphere of these stars,
so it is possible to select a number of spectral lines, that together with other
lines observed in optical spectra, will furnish an unique opportunity to
improve our knowledge about vertical stratification.
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Prog ID: P234
PI: Sankrit, Ravi
Institution: Johns Hopkins University
Title: Extended Grid in the Northeast Cygnus Loop
We will obtain MDRS spectra at two locations near a Balmer filament in
the northeast region of the Cygnus Loop supernova remnant. The first
position will be ahead of the filament and the second will be behind
it. These observations will supplement the spectra taken at three
locations on the filament (part of FUSE program P114). The OVI flux
was found to decrease as a function of position downstream behind the
shock front. Weak emission on the wings of the primary OVI 1032
component was detected at all three locations. The flux in these
weaker components was about the same in all three spectra. The current
observations are designed to measure the OVI flux in regions away from
the filament. This will allow us to examine the OVI emission that may
be present, arising from regions other than the shocked gas in the
Balmer filament. We expect he same strength in each of the spectra.
The current observations are designed to measure the OVI flux in
regions away from the filament. From these measurements we will be
able to estimate the contribution of sources other than the primary
shock to the total OVI flux in the remnant. In addition to the spectra
in the primary aperture (MDRS) we will obtain data in the LWRS aperture,
from which we will obtain the OVI flux in regions about 3.5 arcminutes
away, but still within the remnant.
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Prog ID: P235
PI: Sonnentrucker, Paule
Institution: Johns Hopkins University
Title: H2, metals and DIBs in Reflection Nebulae
Diffuse Interstellar Bands (DIBs) are absorption features detected mainly in
the optical. Even though the DIB carriers have been proven to be most likely
carbonaceous in nature and reside in the gas phase, their origin remains a
complete mystery (Herbig, 1995 for a review). Former studies indicated that
some (DIBs) are weaker in reflection nebulae than in diffuse clouds of
equivalent reddening. Few attempts were made to explain the DIBs peculiar
behavior toward those particular environments. However, this issue widely
remains unexplored because the line of sight properties toward reflection
nebulae are not always well constrained. I, therefore, propose to observe the
reflection nebulae HD190603 and HD198478 to derive the column density of H2,
CI, CI* and CI**, PII, ArI, FeII, NI, estimate the molecular fraction in order
to study these lines of sight properties and relate them to the DIBs, CaI, CaII,
NaI, CH and CH+ column densities measured in the optical. In addition, the
extinction curves of HD190603 and HD198478 only differ in the FUV non-linear
rise portion. Since the FUV non-linear rise is thought to be due to very
small grains (or large molecules) in a neutral form, assessing the role of
the FUV non-linear rise on to the DIBs, H2 and the metals in the FUSE passband
will give further information on the properties of these two lines of sight and
the DIB carriers survival/destruction conditions.
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Prog ID: P241
PI: Lehner, Nicolas
Institution: The Johns Hopkins University
Title: FUSE Observations of the Magellanic Bridge
Young B-type stars are known to exist in the Magellanic Bridge (MB) gas,
a region of material between the Large and Small Magellanic Clouds,
implying that star formation is still occurring in the MB. In all
known environments star formation occurs within molecular clouds,
but there is yet no direct evidence of star-forming clouds in the MB.
FUSE will allow for the first time to make a direct sensitive search
for molecular hydrogen in the MB and give more insights on the possible
star formation mechanisms in low density and metallicity environments.
The proposed targets are two young hot stars, DI1388 and DGIK975, and
not only search for molecular hydrogen will be made possible, but a
detailed investigation of the physical conditions within the MB gas
will be studied in different spatial positon (DGIK975 is near the LMC
while DI1388 is near the SMC). In particular, using our previous HST STIS,
the FUSE observations will allow us to place limit or measurements on the
ratios of C III/C II, S III/S II, N III/N II/N I, Fe III/Fe II, Si IV/O VI
and C IV/O VI. Finally, an HVC was detected in the DI1388 STIS spectra and
was found to be nearly fully ionized. FUSE observations will help to place
a constrain on the ionization origin by studying the ionic ratio of several
species.
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Prog ID: P242
PI: De Marco, Orsola
Institution: American Museum of Natural History
Title: Thermonuclear Runaways on Dwarf Novae
We are going to take an observation of the dwarf nova SS Cygni during
quiescence to measure elemental abundances in the atmosphere of the
exposed white dwarf component of this binary. We expect that the absolute
abundances will yield clues about the past outbursting history of the system.
In particualr, as is the case for the dwarf nova VW Hyi, we might detect
abundaces characteristic of thermo-nuclear processing,
which would indicate that SS Cyg experienced a nova outburst
sometime in its past. Such finding would contribute substantially in unifying
the dwarf nova and nova outburst scenarios.
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Prog ID: P243
PI: Hoopes, Charles G.
Institution: Johns Hopkins University
Title: WR Star AV336a in the HeII Nebula N76-A
I propose to obtain a 10 ksec LWRS spectrum of the WR star AV336a in
the SMC. This star is surrounded by a HeII nebula (Garnett et
al. 1991), one of only six known in the Local Group. The presence of
HeII emission requires that the ionizing star emit photons with energy
greater than 54 eV, which in turn requires a stellar effective
temperature of 70,000 - 80,000 K. Wolf-Rayet stars have temperatures
in the 30,000 - 60,000 K range (Conti 2000), and in fact no population
I stars are known to have temperatures as high as those required by
the HeII emission. Either AV336a is a very rare type of star, or else
the ionization source in this HII region is not understood. The FUSE
bandpass provides a unique opportunity to study both AV336a and the
surrounding HeII nebula. The stellar spectrum will provide information
on the stellar winds and abundances, which will shed light on the
unusual nature of this star. Secondly, the absorption spectrum of the
intervening material in the HeII nebula will provide information about
other highly ionized elements. The adjacent ionization stages of PIII,
IV, and V and S III, IV, and VI in the FUSE bandpass, as well as other
ionized gas diagnostic lines, will be used to measure the luminosity
of the star at energies well above the Lyman limit, providing a strict
diagnostic of the stellar temperature. The spectrum will also be used
to search for high velocity gas that would indicate shock ionization.
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Prog ID: P247
PI: Young, Peter
Institution: Harvard-Smithsonian Center for Astrophysics
Title: 44i Bootis (HD 133640)
44i Boo is a W UMa type contact binary at a distance of
12.8 pc with an orbital period of 6.4 hours and an inclination of 72.8
degrees, so that there are two eclipses per orbit. X-ray and UV
emission from highly-ionised ions have revealed that 44i Boo exhibits
a corona, but that the emission levels are below those of rapidly
rotating single stars or short-period, detached binaries, indicating
that the dynamo is being inhibited by the physics associated with the
contact. By categorising in detail the nature of the corona of 44i
Boo, one may shed light on how the magnetic dynamo operates in stars.
With FUSE it will be possible to use the high spectral resolution and
sensitivity of the instrument to monitor line fluxes and profiles of
the strong C III 977 and O VI 1032 emission lines during the orbit, as
well as use the temperature coverage of these and weaker lines to
compare with the atmospheric models made with previous instruments.
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Prog ID: P248
PI: Young, Peter
Institution: Harvard-Smithsonian Center for Astrophysics
Title: AG Draconis (BD +67 922) Follow-up
AG Draconis is a symbiotic star consisting of a K giant and white
dwarf. The UV is dominated by emission lines from a nebula believed to
be around the white dwarf.
AG Dra was observed by FUSE on 16-March-2000 as part of the science
verification program for FUSE. This short (~2400s) observation
produced a high quality spectrum revealing emission lines from several
species, including O VI, Ne V, Ne VI, S IV, S VI and He II.
A further observation of AG Dra is planned to determine the geometry
of the nebula, attribute the wind to one of the two stars, and to
obtain a full exposure in the SiC channels which will be needed to
obtain a density for the nebula.
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Prog ID: P249
PI: Andre, Martial
Institution: John Hopkins University
Title: HD in a Translucent Cloud
Deuterated molecules are another means of determining the Deuterium
abundance. With Copernicus, H2 and HD nolecules were observed in
absorption in the ultraviolet in diffuse clouds such as that toward
Zeta Oph. Nevertheless, very low HD/H2 ratios were found, reflecting
the atomic nature of these clouds. With FUSE, we can use denser
molecular clouds within which one might expect H and D to be in their
molecular form. In such cases, molecular fractionation correction is
not required and direct measurement of D/H could result from
HD/H2 ratios. Until recently, HD/H2 measurements were limited to these
few good candidates where the velocity structure could allow for an isolated
translucent intervening cloud, but saturation and low S/N of these
detections implied large uncertainties on the result. For one of the
translucent cloud's targets, however, high S/N detection of HD is
present. The star HD206267 lies behind the translucent cloud DC 1107.
Within a few arc min to the star, and showing the same
reddening (E(B-V) ~.4) we found 2 fuv bright stars : BD+56 2617C and
BD+56 2617D. These 3 stars could possibly illuminate the same cloud
whose aera is grater than 10 deg steradian on the sky (very close).
Such a configuration is what we need to argue for a HD reservoir
inside the cloud.
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Prog ID: P250
PI: Roberge, Aki
Institution: Johns Hopkins University
Title: Circumstellar Disk Target HD 141569
The circumstellar disks medium team projects (P119 and Q119) have produced
remarkable spectra, showing emission and absorption features arising
from gasses that have a wide range in temperature, from hot OVI emission to
cold H_2 and CO absorption. The emission from the highly-ionized species was
unexpected, as standard stellar theory predicts that these stars (with spectral
types earlier than about F0) should not have convective outer layers, and
therefore, should not have chromospheres, coronae, or strong stellar winds.
While these stars clearly do show stellar activity, the exact nature is
unclear. AB Aurigae shows strong stellar winds and it is thought that
the highly-ionized species may be formed by shocks in the wind. Beta Pic,
on the other hand, shows emission from OVI and CIII, but no trace of
stellar winds. Since Beta Pic is older than AB Aur, this difference
might indicate that the stellar activity is changing (possibly decreasing)
with age. To demonstrate this, we need to study young stars with a variety
of ages. Unfortunately, most of the targets in P119 and Q119 are younger
than about 10 Myr; Beta Pic is the only one that is clearly older
(age ~ 20-30 Myr). We therefore propose to observe another nearby young
star with a CS disk, HD 141569 (spectral type B9 Ve, d=99 pc), that is
thought to be a more evolved object (age > 10 Myr).
This star's CS disk was imaged with NICMOS (Weinberger et al. 1999), which
showed a remarkable gap in the dust disk. This gap may most easily be
explained by the gravitational influence of one or more planets orbiting
the star. (Go to http://oposite.stsci.edu/pubinfo/pr/1999/03/index.html to
see the NICMOS image and HST press release). This makes HD 141569 a very
interesting object, as well as providing additional evidence that it is a
relatively evolved young star.
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Prog ID: P251
PI: Oliveira, Cristina
Institution: Johns Hopkins University
Title: D/O ratio toward WD2247+583
I propose to observe the white dwarf WD2247+583 (Lan 23) and
measure the D/O ratio along this line of sight.
If the O/H ratio is ~ constant as the work of Meyer et al (ref 3) seems to
indicate and the D/H is also ~ constant then we would expect that D/O is
also ~ constant. Preliminary analysis of several lines of sight using FUSE
data have not yet been able to show a definite correlation between N(DI)
and N(OI) and so more measurements along different lines of sight are
needed.
Previous measurements using EUVE data (ref 1) have placed the HI column
density at 716 < N(HI) < 1596 x10^17 cm^-2. Using a D/H ratio of 1.2x10^-5
this places the DI column between 8.6 x10^14 and 1.9x10^15 (cm^-2).
This will be an interesting measurement since DI is typically measured in
lines of sight with low HI column density (N(HI)~10^18 cm ^-2) and we'll
be probing the D/O ratio in a regime that is not very explored.
The effective temperature and gravity of this white dwarf indicates that
the stellar continuum will be relatively smooth and continuum placement
won't be a major uncertainty in measuring N(DI) as is the case with other
types of white dwarfs.
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Prog ID: P252
PI: Pellerin, Anne
Institution: Universite Laval
Title: Young Stellar Populations and the Starburst-AGN Connection
I propose to study young stellar populations in the nuclear
region of the starburst galaxy NGC 5430. This project is part
of my thesis which adresses the question of an evolutionary
relation between nuclear starbursts and AGN (based on Weedman et
al. 1998 and Heckman et al. 1997). For my thesis, a large sample of starbursts
and AGNs are to be considered in order to establish a scenario on
how nuclear starbursts may evolve into an AGN based on the importance
of a nuclear bar (Friedli et al. 1995). Although the FUSE archives
already contain spectra for a variety of nuclear starbursts and AGN,
none of them are characterized by a strong nuclear bar. The goal of
this proposal is to obtain a FUV spectrum of the starburst galaxy
NGC 5430, which does have such a bar.
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Prog ID: P263
PI: Wilkinson, Erik
Institution: University of Colorado
Title: Pre-Main Sequence Stars
HST/STIS GTO observations of HD104237 are being planned during 2001
using 4 HST orbits to observe the star using 2 orientations of
coronagraphic imaging, and then obtaining two UV spectra, one a G140M
spectrum at H Lyman alpha with an orientation determined from the
coronography, and the other a G140L spectrum with the same orientation.
We would like to obtain a second epoch FUSE observation
of HD104237 contemporaneous with the STIS UV spectroscopy, in order
to measure the full temperature structure of the circumstellar
environment around this young intermediate mass star and to investigate
whether the FUV spectrum of this star is as variable as the spectra from
other Herbig Ae stars.
This star has very few HST observing constraints and thus FUSE
observation scheduling can be the primary driver for when these
observations occur.
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Prog ID: P267
PI: Green, Jim
Institution: CASA, University of Colorado
Title: Extragalactic Hot Gas along the MRK1383 sightline
HST/STIS+G140M data of the MRK1383 sightline reveal
an extremely broad, but relatively weak, low-z Ly-alpha absorber.
We propose to use FUSE to search for OVI absorption
associated with this absorber to search for hot gas in the
very local universe.
===============================================================================
FUSE PI-Team Cycle 3 Small Programs
Prog ID: P323
Title: Supernovae as Probes of Galactic Halos
PI: Sembach
FUSE observations of a newly discovered, bright (V<14) core-collapse supernova
(Types II or Ib) will be used to study interstellar properties of the sightline.
The full range of interstellar species present in the FUSE wavelength range will
be utilized to examine kinematics, depletions, and abundances of foreground gas,
the Milky Way halo, the ISM of the supernova's host galaxy, and the intergalactic
medium. Any data obtained from this program will be made available to other FUSE
programs to study the properties of the supernova outburst.
FUSE French Guaranteed Time Observing Programs (Cycles 1, 2, and 3)
----------------------------------------------------------------------------
Prog ID: Q101
Title: H_2 Associated with Dust Color Variations
PI: Gry
Institution: Laboratoire d'Astrophysique de Marseille and ISO Data Center
We propose to study the H_2 excitation, as well as the H_2 abundance and
velocity distribution in nearby diffuse clouds in the Chamaeleon complex.
The selected lines of sight present a wide variety in infrared colors,
E(B-V), Rv and molecular abundances so that we can check the dependence of
H_2 properties with these characteristics. After IRAS data revealed
spatial variations in the dust emission color of these clouds, these
variations have been correlated with changes in the shape of the UV part of
the extinction curve, showing that they are due to variations in the size
distribution of small dust particles. Comparative studies in the
millimeter, visible and UV ranges have shown that highly energetic
processes are present in the cloud presenting mid-IR excess.
Magnetohydrodynamic shocks and intermittent dissipation of turbulence have
been considered. The proposed study of H_2 in these clouds will help
characterize these processes which should be of great significance for the
evolution of dust particles and of the gas itself.
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Prog ID: Q103
Title: He I in Local ISM
PI: Vidal-Madjar
Institution: Institut d'Astrophysique de Paris
An attempt will be made on the brightest EUVE source showing emission in
the 600 Angstrom EUVE band (410 c/ksec), to try to detect some second order
absorption signature corresponding to He I in the local ISM.
----------------------------------------------------------------------------
Prog ID: Q105
Title: Lyman Break in Star-Forming Galaxies
PI: Deharveng
Institution: Laboratoire d'Astronomie Spatiale
We wish to observe a star-forming galaxy shortward of its (rest frame)
Lyman limit in order to measure or set limits on the Lyman continuum escape
fraction. An object with a redshift large enough to get rid of residual
galactic gas absorption (lyman series) is selected. Another related goal
is to use the spectrum longward of the Lyman limit for better understanding
the star, dust and gas content of the galaxy.
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Prog ID: Q106
Title: O VI Phase in Galactic Haloes
PI: LeBrun
Institution: Laboratoire d'Astronomie Spatiale
We propose to make low resolution (R=2000 and S/N~20) observations of two
quasars, 3C 351 and Mark 205. Their sightlines cross the near environment
of already known and identified galaxies or groups of galaxies, at impact
parameters in the range 40-700 kpc (H0 = 50 km/s/Mpc). We will be able to
detect the O VI doublet lines in absorption down to a limiting equivalent
width of 0.2 Angstrom. We thus plan to determine whether a highly ionized
phase exists in the close galactic environment in which the cooler and
denser MgII absorbers would be embedded. These observations will also help
in determining whether collisional excitation is present in these clouds
and also to study the evolution of the shape and intensity of the
intergalactic UV flux at low redshift.
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Prog ID: Q107
Title: H_2 in the Small Magellanic Cloud
PI: Ferlet
Institution: Institut d'Astrophysique de Paris
The star Sk 143 in the SMC has most peculiar properties: its extinction
curve in the far-UV is of Galactic type, contrary to all the other SMC
stars which have a small or absent extinction bump and a very strong rise in
the extinction at shorter wavelength. It also has an apparently Galactic ratio
of E(B-V) to atomic hydrogen column density. Still, the interstellar lines are
at the SMC velocity, and suggest that the extinction is due to a molecular
cloud in the SMC. However a deep integration in the CO(1-0) line with the
Swedish-ESO submillimeter telescope has given a null result. FUSE will help
solve this mystery by observing the H_2 lines and other lines which might
yield a detection of the absorbing gas.
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Prog ID: Q108
Title: Central Stars of Planetary Nebulae
PI: Vidal-Madjar
Institution: Institut d'Astrophysique de Paris
Several investigations will be done simultaneously by observing the central
stars of some bright Planetary Nebulae (PN):
(a)The wavelength range is particularly appropriate to study the continuum,
the temperature and the wind of the PNe central stars;
(b)In addition to the stellar continuum, the spectra will yield information
concerning the nebula. The CIII line at 977A should be easily observable.
Its intensity will be an additional independent measurement to resolve
the controversy about the carbon abundance in PN;
(c)FUSE will offer the possibility to detect molecular hydrogen
lines in absorption against the stellar continuum. In several cases,
the velocity separation of that component formed in the vicinity of the
nebula and that formed in the general ISM will be possible. It should
then be possible to determine how much additionnal H_2 is formed by
shocks in the stellar winds.
(d)Finally, the non detection of deuterium should allow a direct check of its
evolution within stars since these PN were selected for their different 3He
environment.
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Prog ID: Q109
Title: Peculiar White Dwarfs
PI: Vidal-Madjar
Institution: Institut d'Astrophysique de Paris
The standard post-AGB evolution theory predicts that throughout the
whole post-AGB phases the chemical surface composition of the star remains
essentially unchanged, because hydrogen shell burning ceases when the
surface H-rich layer has been thinned down to about 1.e-4 Msun. However
about 25% of the spectroscopically observed post-AGB stars in the planetary
nebula stage are hydrogen-deficient and the origin of their peculiar
surface abundances is still unclear. Among the hydrogen deficient post-AGB
stars the class of the PG1159 stars are the most peculiar. They cover the
hottest part of the post-AGB evolution (65000 - 180000K) and their surface
is composed of carbon, helium, and oxygen (typically 50/30/20% by mass).
Since mass loss could also be responsible for the observed peculiarities,
we need a determination of the mass-loss rate to be conclusive. The O VI
line at 1034 Angstroms is best suited since it is the most sensitive
indicator for mass-loss in these stars. In that frame we will observe
PG1159-035 the prototype as well as H1504+65 which is the most extreme one
of this class. Deuterium evaluations will be also made on the line of
sights towards these stars.
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Prog ID: Q110
Title: Quasi-Molecular Satellite Lines in Lyman Beta
PI: Vidal-Madjar
Institution: Institut d'Astrophysique de Paris
Our purpose is to detect in the wing of Lyman Beta the signatures of
absorptions due to the quasimolecular satellites of H_2+ and H_2 in,
respectively, photospheric spectra of a white dwarf and a Lambda Boo star
where they have been observed in wing of Lyman Alpha. These targets are
suitable for such detection: the white dwarf WD1620-391 has a pure hydrogen
atmosphere and that of HD125162 is depleted in metals.
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Prog ID: Q111
Title: The Symbiotic Binary IX Velorum
PI: Ferlet
Institution: Institut d'Astrophysique de Paris
The profiles of the absorption and emission lines, particularly of the O VI
doublet for the symbiotic binary AG Peg, will enable information to be
obtained on the kinematics of the regions of line formation. The very high
ionization O VI doublet may in particular be produced very near the compact
hot component. A wind from the cool component of the binary should be
present; signs of the continuing existence of a wind from the hot component
seen on older IUE spectra as well as a possible region where the winds
collide, will be looked for.
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Prog ID: Q112
Title: Cataclysmic Binaries
PI: Ferlet
Institution: Institut d'Astrophysique de Paris
We propose to observe the highly mass-accreting cataclysmic binary IX Vel
in the far UV, for the first time at a very high spectral resolution
(R~30000), to infer the physics of the accretion very close to the white
dwarf. A detailed analysis of the absorption resonance lines of O VI, PV
and SVI by means of phase-resolved spectra (exposure time of 1/8 Porbital)
will bring important clues to probe the structure of the wind (geometry,
velocity law, inhomogeneities). When combined with the study of the
continuum distribution in the far UV, this will allow us to test the still
unknown mechanism of wind formation and to distinguish between different
proposed models for the boundary layer which plays a major role in the
dynamical evolution of these systems.
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Prog ID: Q113
Title: The Old Nova V603 Aql
PI: Ferlet
Institution: Institut d'Astrophysique de Paris
The absorption and emission line profiles of the old nova V603 Aql will
be observed with FUSE in order to further study the properties of what
appear to be an accretion disk and wind coming from this disk, also studied
at longer wavelengths. Rapid line profile variations already seen for
other lines in HST spectra, will in be searched for and examined, this
being the case in particular for the O VI doublet.
----------------------------------------------------------------------------
Prog ID: Q114
Title: Be Stars
PI: Ferlet
Institution: Institut d'Astrophysique de Paris
The study of high excitation line transitions in the wavelength range
observed by FUSE will bring important information on the nature of
activities taking place in the outermost layers of Be stars. The Lyman
energy distribution predicted by thermal models of stellar atmospheres,
which does not even agree with observations of normal B stars, will
probably produce larger disagreements in Be stars, where, as highly
rotating objects, the atmospheric structure remains quite unknown. A young
B star in a binary system with a T-Tauri star will also be observed for the
purpose of comparison. This program is also conducted in the frame of
other observing programs toward B and Be stars.
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Prog ID: Q119
Title: Circumstellar Disks
PI: Deleuil
The purpose of this program is to give new insights on the signatures of
circumstellar gas around main-sequence and pre-main-sequence stars. For
the stars Beta Pic (HD39060) and 51 Oph (HD158643), the gas already
detected may be the by-product of some activity (like evaporation and/or
collision of kilometer-sized bodies) in a young planetary system in its
clearing out phase. These observations are expected to allow the
identification of the main form of the gaseous phase (H_2, CO, OI, NI, CII
?) and to give information on the ionization equilibrium of the zero radial
velocity as well as accreting gas. Analysis of multiplet ratios will allow
to probe the sizes of the inflowing gas structures.
----------------------------------------------------------------------------
Prog ID: Q201
PI: Gry, Cecile
Institution: Laboratoire d'Astrophysique de Marseille and ISO Data Center
Title: IS Studies : H2 associated with dust color variations
We propose to study the H2 excitation, as well as the H2 abundance and
velocity distribution in nearby diffuse clouds.
This is to complement the study started with Q101 for clouds in
the Chamaeleon complex.
The selected lines of sight present a wide variety in infrared colors,
E(B-V), Rv and molecular abundances so that we can check for correlations
between these characteristics and H2 properties.
After IRAS data have evidenced spatial variations in the dust emission
color of these clouds, these variations have been correlated with changes
in the shape of the UV part of the extinction curve, showing that they are
due to variations in the size distribution of small dust particles.
Comparative studies in the millimeter, visible and UV ranges have shown
that highly energetic processes are present in the cloud presenting mid-IR
excess. Magnetohydrodynamic shocks and intermittent dissipation of turbulence
have been considered. The proposed study of H2 in these clouds will help
characterize these processes which should be of great significance for the
evolution of dust particles and of the gas itself.
----------------------------------------------------------------------------
Prog ID: Q206
PI: Le Brun, Vincent
Institution: Laboratoire d'Astronomie Spatiale
Title: O VI Phase in Galactic Haloes
This program is the continuation of the Q106 program on the study of the
OVI phase in galactic halos. We have selected a third quasar, Q0026+1259
(Bowen & Blades, 1997). Two galaxies lie close to the quasar sightline,
which could give rise to OVI absorption lines, which FUSE only would be
able to detect. The quasars has a flux of 2x10^-14 erg/s/cm^2/A.
----------------------------------------------------------------------------
Prog ID: Q210
PI: Hebrard, Guillaume
Institution: Institut d'Astrophysique de Paris
Title: Quasi-Molecular Satellite Lines in Lyman Beta
Quasi-molecular satellites provide an important source of opacity in
the DA white dwarf atmospheres not only in the red wing of Lyman alpha,
but also in the red wing of Lyman beta. The recently discovered line
satellites in the red wing of Lyman beta due to the close collisions of
atomic hydrogen with protons fall right on the range of maximum
sensitivity of FUSE (1050 - 1100 A). This spectrum region has a
great potential for determining basic stellar parameters, provided
that the physics underlying its formation is well described. This is
exactly what we are able to achieve. We propose to observe one DA
cool white dwarf in order to study the temperature
sensitivity of the Lyman beta spectrum and deduce the lower limit of
appearence of these line satellites.
----------------------------------------------------------------------------
Prog ID: Q219
PI: Lecavelier, Alain
Institution: CNES, Institut d'Astrophysique de Paris
Title: Circumstellar Disks
The purpose of this program is to obtain spectra of a new target for the
circumstellar disk program (P119, Q119) which aims to observe the signatures
of circumstellar gas around main-sequence and pre-main-sequence stars.
The selected target HD 163296 is a well known active HAeBe star. It is
surrounded by a circumstellar dust and gas. Episode of accretion and outflows
have been discovered with HST.
A remnant H2 similar to the one detected with FUSE toward AB Aur
(Roberge et al. 2001) could be observed.
In any case, the comparison with AB Aur will be very fruitful.
----------------------------------------------------------------------------
Prog ID: Q221
PI: Andre, Martial
Institution: The John Hopkins University
Title: Red Rectangle Nebula
The Red Rectangle is a remarkable bipolar nebula associated with the
star HD 44179. First studied by Cohen et al (1975), the nature of this
nebula is still not well understood. High-resolution infrared imaging
Mekarnia et al (1998) showed that the nebula is produced by a compact
equatorial disk of dust. Far ultraviolet observation of this nebula may
be an enormous benefit to the study of evolving disk systems, leading
to the best source information along with previous spectroscopic
studies.
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Prog ID: Q222
PI: Deleuil, Magali
Institution: Laboratoire Astrophysique de Marseille
Title: The H2 molecular gas in the center of M100
We propose to observe the central region of the nearby spiral galaxy M100
in order to properly measure the column density of the molecular
hydrogen gas via its absorption lines (Lyman and Werner bands). CO (J=1-0)
data are available for this galaxy as well as metallicity measurments
within the same aperture as that of FUSE.
Therefore we will be able to perform a direct measure of the CO to H2
conversion factor in a normal spiral galaxy.
----------------------------------------------------------------------------
Prog ID: Q223
PI: Ferlet, Roger
Institution: CNRS, Institut d'Astrophysique de Paris
Title: Study of Mkn36
Mkn36 is known to be a blue compact galaxy presenting a relatively
low metallicity. The purpose of this investigation is to search for
H_2 in the context of an intermediate metallicity object.
These observations should also give access to a more precise
evaluation of the elements abundances within such a galaxy as well
as the physical state of the absorbing gas.
If the stellar component responsible for the UV light is well
placed behind absorbing material presenting a small enough spread of
the velocity distribution including thermal, turbulent and large
motion broadening, then possibly an estimation of the deuterium
abundance in such a low metallicity object could be attempted.
In such a case possible follow up observationbs will have
to be considered.
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Prog ID: Q224
PI: Lemoine, Martin
Institution: CNRS
Title: ISM in IZW36
IZW36 is known to be a blue compact galaxy presenting a relatively
low metallicity. The purpose of this investigation is to search
for H_2 in the context of an intermediate metallicity object.
These observations should also give access to a more precise
evaluation of the elements abundances within such a galaxy as
well as the physical state of the absorbing gas.
If the stellar component responsible for the UV light is well
placed behind absorbing material presenting a small enough spread of
the velocity distribution including thermal, turbulent and large
motion broadening, then possibly an estimation of the deuterium
abundance in such a low metallicity object could be attempted.
In such a case possible follow up observationbs will have
to be considered.
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Prog ID: Q225
PI: Vidal-Madjar, Alfred
Institution: Institut d'Astrophysique de Paris
Title: Star formation in the atypical S0 galaxy NGC 5102?
NGC 5102 is a very atypical giant lenticular galaxy: (1) its ultraviolet
emission is much stronger than in other early-type galaxies observed by
the IUE satellite; (2) it is a gas-rich galaxy where HII regions have been
detected; (3) individual observations of blue stars near the center of the
galaxy with the FOC/HST suggest they are young massive stars (Deharveng et
al. 1997). All these results are evidences of a recent star-forming event.
As shown by HUT observations of other early-type galaxies (Brown et al. 1995),
NGC 5102 should also have a population of hot old stars (post-AGB, hot
horizontal branch, AGB manque stars) contributing to the ultraviolet emission.
Between 900 and 1200 A, the spectrum is very sensitive to the temperature of
the hottest stars: FUSE data should therefore be especially efficient to
disentangle the young hot stellar populations from older ones.
To this purpose, the spectral energy distribution will also be connected to
IUE data and optical and near-infrared colors.
The global spectrum (continuum and stellar lines) will finally be analyzed
with our evolutionary synthesis model PEGASE (Fioc & Rocca-Volmerange 1997,
2000) in terms of star formation history and metallicity.
Modeling the spectral energy distribution of NGC 5102 is essential to
understand both the star-forming process in ellipticals and S0's and to
analyze observations of such galaxies at high redshift, when they underwent
star formation. This will put important constraints on cosmological models of
galaxy formation.
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Prog ID: Q301
Title: Extra-solar Planet Aurorae
PI: Vidal-Madjar
Institution: Institut d'Astrophysique de Paris
We will search for extra-solar planet aurorae emission (HI, H2) in the spectrum
of stars with known extra-solar planets. The selected targets harbor "hot
Jupiter" type planets or/and multiple systems. The observations will be
performed during the quadrature to optimize the chance of detection
using the velocity Doppler shift of the planets.
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Prog ID: Q302
Title: Quasi Periodic Oscillations in the accretion disk of Black holes.
PI: Andre
Institution: Institut d'Astrophysique de Paris
Quasi Periodic Oscillations (QPOs) in the X-ray brightness of neutron star and
black hole X-ray binaries provide a useful probe into the inner accretion flows.
Since the discovery in 1985 (Van der Klis) numerous neutron star QPOs have been
observed with properties that depend on the spectral type of the sources (high
or low luminosity). In current nomenclature, we distinguish 8 types of neutron
star QPOs (from kHz to Hz and below). As to the black hole QPOs, a few cases
have been observed in the same frequency range and show many similarities with
neutron star QPOs. Nevertheless, at present the BH QPO studies are based on very
few objects (Dimitrios 1999). Many theoretical models have been proposed for the
different QPOs. Some of them identify the frequency with Keplerian orbital
motion others suggest a hydrodynamic pulsation in the disk, others again imply
general relativistic effects. But some of these models only apply to neutron
star QPOs (hard surface, magnetic field) and some others only to BH QPOs.
Opening the FUV window, FUSE will allow for the study of highly ionised species
in the accretion disk. In particular, the O VI doublet ratio will help to put
a limit on the density of these disk and the broadening of these lines should
also put a constraint on the Keplerian model. Since BH QPO are found to be
consistently lower than the neutron star QPOs, we suggest also the possiblity
of time resolved spectroscopy (~.1 hz) in TTAG mode. The objects we propose to
observe have been selected on a wide variety of criteria : weak stellar
continuum, low distance and low frequency QPO.
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Prog ID: Q303
Title: P cygni line variability in WR 140
PI: Gry
Institution: Laboratoire d'Astrophysique de Marseille and ISO Data Center
WR140 is going through periastron passage of its 7.94-year eccentric
orbit in February 2001. X-ray monitoring with RXTE has shown that the
heavy X-ray absorption expected as the Wolf-Rayet star moves into the
line-of-sight to the O-star primary has started.
Previous IUE observations have shown considerable
extra absorption in P Cygni profiles was seen even months later. Nearer
periastron these absorbtion effects should be much more pronounced.
Although the interstellar absorbtion is quite high to WR140, the region
longward of 1100 A has several lines of interest that should show heavy
absorption through the WR wind. The object will be observed once during
the periastron passage and once several months later to evidence the
variations.
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Prog ID: Q304
Title: The rapidly evolving planetary nebula Hen 3-1357
PI: Gry
Institution: Laboratoire d'Astrophysique de Marseille and ISO Data Center
Hen 3-1357 (known as the 'Stingray Nebula') is the youngest Planetary Nebula
known in the sky. It has become ionized within the past few decades and its
central star seems to be still rapidly evolving in the H-R diagram towards
hotter effective temperatures. With this proposal we want to determine the
current effective temperature of the central star and the characteristics
of the stellar wind thirteen years after its discovery with IUE.
This will enable us to determine whether the rapid spectral
changes observed in the last few years are the consequence of an
episodic post-AGB mass loss event or the result of a continuous
evolution in the H-R digram. In any of these cases, the observations will
help us to understand this short and, thus, still poorly known transition
phase which leads to the formation of a new PN.
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Prog ID: Q305
Title: Lyman continuum radiation from galaxies
PI: Deharveng
Institution: Laboratoire d'Astronomie Spatiale
There is an on-going effort to measure the Lyman continuum radiation
escaping from galaxies. Current data suggest a cosmic evolution of
the escape fraction with implications on the contribution of star
formation to the ionisation of the intergalactic medium. Measurements
of nearby galaxies with FUSE should confirm the trend observed.
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Prog ID: Q306
Title: Search for H2 in young circumstellar disks
PI: Lecavelier
Institution: Institut d'Astrophysique de Paris
We will search for H2 absorption lines in the spectrum of stars surrounding
by circumstellar disks in which H2 is already detected through quadrupole
rotational transitions.
By observing different inclination of disks, these observations will constrain
the spatial distribution of the molecular gas. This should help to solve the
issues raised by the observations of H2 in the Beta Pictoris disk.
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Prog ID: Q319
Title: Circumstellar disks
PI: Deleuil
Institution: Laboratoire d'Astronomie Spatiale
The purpose of this program is to obtain spectra of new targets for the
circumstellar disk program (P119, Q119, P219, Q219) which aims to observe
the signatures of circumstellar gas around main-sequence and pre-main-sequence
stars. HD 141569 is a well-known pre-main sequence stars surrounded by a
circumstellar disk for which images have been obtained, given information
on the dust distribution and inclination of the disk.
HD 36112 is a young pre-main sequence star surrounding by a huge amount of CO.
The derivation of the CO/H2 ration will give important information on the
gaseous content as well as on the origin and history of disk around stars more
massive than the Sun.
