Cycle 7 - Phase 1 Abstracts 1/19/06 AFB Prop ID: G001 Proposer: Wang Institution: University of Massachusetts Proposal Title: OVI Emission from Galactic Disk-Halo Interaction We propose FUSE observations to sample the OVI line emission from the disk-halo interaction of the nearby galaxies NGC2841 and NGC7090. The OVI line emission traces the gas at temperatures near the peak of the cooling curve and can be compared with the X-ray radiation from the hotter component (Tgtrsim1times10^6,K), as detected in our deep Chandra observations, and with the mechanical energy input from supernovae in these galaxies. The line intensity measurements will help to determine the temperature distribution and cooling mechanism of the hot gas, whereas the line centroids and widths of the emission will further enable us to study the line-of-sight size and dynamics of the gas. The results will have strong implications for understanding the role of the disk-halo interaction in galactic eco-systems. endabstract Prop ID: G002 Proposer: Meyer Institution: Northwestern University Proposal Title: High-Velocity Molecular Gas Toward M81 Multiwavelength observations of the M81 galaxy group have discovered several dwarf galaxies and molecular complexes that may be associated with the intergalactic gas in this interacting system. Although HI 21cm observations have found no evidence of such gas toward the M81 nucleus, opticalUV spectroscopy has revealed high-velocity atomic absorption in this region. We have recently found a strong NaI component at +217kms^-1 that stretches over 400pc WSW of the nucleus. In order to probe the molecular content of this high-velocity gas, we propose to obtain FUSE observations of the H_2 absorption in the central AGN sightline. Our anticipated N(H_2) detection threshold of 5x10^15cm^-2 is five orders of magnitude more sensitive than that inferred from the lack of CO 2.6mm absorption toward the central source. If we fail to find H_2 at this sensitivity, it would imply that the high-velocity gas toward M81 is entirely atomic and thus analagous in content to the non-Magellanic-Stream HVCs in the Galactic halo. On the other hand, the detection of an appreciable H_2 column would indicate that this gas has formed or is forming molecules and is most likely tidally-stripped material from M82. Prop ID: G003 Proposer: Oliveira Institution: Johns Hopkins University Proposal Title: HI, DI and other abundances along three extended sightlines Measurements of the DH and DO ratios have been shown to be remarkably constant up to log N(H) 19.2, which corresponds roughly to the limits of the Local Bubble. Between 19.2 < log N(H) < 20.6, these ratios present a large scatter, while for log N(H) > 20.6 DH and DO seem to be constant again, albeit with values roughly half that of the Local Bubble. Although several mechanisms have been proposed to explain these variations, a global consistent picture of these abundance patterns is still missing. The low yield of high column density sightlines suitable for accurate DH measurements has been a major barrier to progress in this area. This derives from the extreme difficulty of finding suitable targets at these high N(H), both in terms of DI not being obscured by either HI or H_2 absorption and having data available to determine reliable N(HI) from Lyman alpha. This proposal requests additional observing time to obtain signal-to-noise ratios adequate for determining the column densities of DI, NI, OI, and FeII, along three high N(H) sightlines that have been previously observed by FUSE. Preliminary analyses of the current datasets show that these sightlines are suitable for DI measurements and that they may have high DH ratios (> 1E-5). Existing high resolution HST/STIS data for the three sightlines will be used to determine N(HI) along two of the sightlines (N(HI) has been published for the other one) as well as to model the velocity structure along the sightlines. These datasets will also allow us to determine the abundances of species that do not have unsaturated transitions in the FUSE bandpass (SI, NiII, etc.). Additionally, N(OI) derived from the weaker, but with a more reliable f-value, 1356AA transition in the STIS bandpass will be compared to the one derived from the 974AA transition in the FUSE bandpass. Prop ID: G004 Proposer: Lauroesch Institution: Northwestern U. Proposal Title: Prospecting for Rare Elements in the Interstellar Medium The complex history and evolution of element production is reflected in the abundance ratios. The distinctive abundance patterns produced by nucleosynthesis in supernovae and stars can be used to explore the history of star formation and evolution in galaxies. Recent observations of damped Lyman-alpha absorbers suggest that observations of r- and s-process elements at high redshifts will soon provide a new window to explore chemical evolution. Paradoxically, we may soon have more detections of some elements in high redshift galaxies than in the Galactic ISM. However, without an understanding of the depletion behavior of these elements based upon observations of nearby sightlines we will be unable to correctly disentangle the effects of dust depletion and nucleosynthesis. We therefore propose to determine the depletion of r- and s-process elements in two Galactic sightlines with relatively mild depletion patterns on nearly opposite parts of the sky. In addition to providing a baseline for studies at high redshift, the long pathlength studied allows us to search for abundance variations within our Galaxy. Absorption lines of the dominant ionization state of these elements can only be detected in the UV, and FUSE is the only current instrument that can make progress in this field. Prop ID: G005 Proposer: Schmidtke Institution: Arizona State University Proposal Title: BeX-ray Pulsars in the Small Magellanic CLoud BeX-ray pulsars are the most numerous type of high-mass X-ray binary HMXB) found in the SMC, with over thirty known. Yet, not one of this important class has been observed by FUSE. We propose to obtain FUSE data for two of these systems which are well studied optically the classical source SMCX-3 and AXJ0049.4-7323. Our FUSE spectra will not only be the first far-ultraviolet spectra of SMC BeX-ray pulsars, but will also have sufficient pulse-phase resolution to investigate the behavior of the material in the vicinity of the neutron star as the pulsar beam sweeps through it. We will study variations in strength and profiles of the expected He II and O VI emissions from this gas to understand how the ionization and excitation changes through the pulse period. AXJ0049.4-7323 is particularly well suited to such a study with its very long X-ray pulse period (755 sec). SMCX-3 has a much shorter pulse period (7.8 sec), but it is sufficiently bright that we can bin the raw data into pulse-phase resolved spectra. This study will provide FUV spectra of the important but unobserved HMXB and will give unique information about the environs of the neutron stars. Prop ID: G006 Proposer: Gull Institution: Goddard Space Flight Center Proposal Title: Separating Binary Orbital Variations in Eta Carinae from Secular Changes Eta Carinae has long been suspected to be a massive binary system, but the hot companion has eluded detection until now. Our FUSE Cycle 4 observations have revealed the hot companion of eta Car for the first time. FUV spectra show that the companion is consistent with a late O or WR star, possibly nitrogen rich. FUSE observations of eta Car now span one complete binary orbit (5.54 years). Future FUSE spectra will allow us to begin to separate cyclical binary orbit variability from long-term secular changes. We propose two Cycle 7 observations about six months apart to place further constraints on the hot companion, perhaps obtaining spectral classification and radial velocity measurements which could lead to direct mass estimates for the system. These objectives are supported by spectral analysis of STIS observations from 1998.0 - 2004.5 that are yielding radial velocity curves for the wind-wind interaction in the binary system. Prop ID: G007 Proposer: Henry Institution: The Johns Hopkins University Proposal Title: Diffuse UV Background web site. We show that FUSE is capable of providing unique data on the diffuse ultraviolet background radiation shortward of Lyman Alpha. This is the only way of confirming previous Voyager measurements of the diffuse background, which are contaminated with Lyman Beta because of the poor (28 AA) spectral resolution of Voyager. Confirmation of the Voyager measurements is important in its own right, but also may be of unique importance to cosmology, as the Voyager measurements show a drastically different picture of the diffuse ultraviolet background short of Lyman Alpha, compared with what is seen longward of Lyman Alpha, suggesting the possibility that the general diffuse background longward of Lyman Alpha is at least partially of cosmological origin (intergalactic hydrogen recombination radiation). While we have just, once again, been successful in obtaining GALEX observing time longward of Lyman Alpha, FUSE provides our only opportunity to test the strength of our case shortward of Lyman Alpha. Prop ID: G008 Proposer: Ignace Institution: East Tennessee State University Proposal Title: Non-Spherical Winds and Disks around Rapidly Rotating, Luminous Stars The role of rotation for the mass loss from massive stars, with relevance for their evolution, is an important topic for which a number of outstanding questions persist. Chief among the puzzles is the creation and maintenance of disks observed around some evolved massive stars -- the supergiant Be (sgBe) stars and Luminous Blue Variables (LBVs). We are seeking FUSE time to observe 4 stars of these types in the Magellanic Clouds. The goal will be to analyze the wind lines to further our understanding of the wind structure, to restrict the inclination of the systems, and to derive the possible rotation velocity of the central stars. We expect to probe the faster polar wind with higher ionization lines (SIV, FeIII, PV) and lower ionization lines to probe the disk flow (OI, NI, FeII). The presence of OVI would also be a tracer of hot gas in system, a common feature of line-driven flows. Prop ID: G009 Proposer: Welsh Institution: UC Berkeley Proposal Title: The W4 Superbubble We propose to examine the high velocity ionized and neutral interstellar gas associated with the expansion of the W4 superbubble. The massive young star clusters of IC 1805 & IC 1848 appear to be to be powering an outflow of gas, such that the interstellar cavity has reached the classic bubble blow-out evolutionary phase and is now in the stage of ejecting gas through a galactic chimney into the overlying galactic halo. By comparing the interstellar sight-lines towards two early-type stars associated with underlying IC 1805 & IC 1848 clusters with a sight-line that intersects the arching chimney of expanding gas that has blown out into the lower halo, we shall be able to investigate the physical, chemical and dynamic conditions of the disturbed atomic and molecular gas associated with a classic blow-out phenomenon. Prop ID: G010 Proposer: Wakker Institution: University of Wisconsin Proposal Title: Studying the Warm-Hot Ionized Medium in Groups of Galaxies When comparing the inventory of baryons in galaxies with determinations of Omega_b obtained from deuterium and the 3K background radiation, most of the baryons appear to be missing. They may be hiding in the warmhot intergalactic medium WHIM) which can be observed through intervening OVI and NeVIII absorption line systems; about 50 of these have now been found. However, it remains unclear whether these systems are truly intergalactic or whether they are associated with galaxies andor galaxy groups. This relation is best studied at very low redshift v<6000kms, z<0.02), where we have a good galaxy inventory and can also study the 21-cm and X-ray properties of the IGM. Associated OVI and Lyman beta is seen in about 60 with AGN-galaxy impact parameter <300kpc, but we find just one detection in seven sightlines with SN>10 that pass through a nearby loose group. We propose to search for OVI and CIII absorption toward RX,J1830.3+7312, which is one of just two known targets with flux >1.3tfu that pass through the inner half of a nearby group. Lyman Alpha has already been detected in its HST spectrum, including a broad line that may originate in hot gas. Prop ID: G011 Proposer: Wakker Institution: University of Wisconsin-Madison Proposal Title: Hot Gas in the Central Region of the Milky Way Understanding the distribution, kinematics and origin(s) of the hot T>dex5K) interstellar gas in our Galaxy is one of the major goals of the FUSE mission. A large amount of hot gas is expected to be present in the Galaxys central region, as a result of stellar winds from OB stars, supernovae, and possibly even activity in the central black hole. The expected levels of activity may even produce an outflow of gas. We have a program to investigate OVI in the central few kpc of our Galaxy, by pairing extragalactic sightlines with galactic targets at known distances. This strategy allows us to differentiate between hot gas in the foreground and gas in the central region or beyond. We have identified several such pairs. High-positive and high-negative velocity OVI is seen in most extragalactic targets but not in the stellar targets, suggesting the presence of gas associated with the Center. However, the data are not good enough to be confident of this conclusion. We thus request additional data for four of the targets at declination >-50deg, as well as an exposure on a new target. Prop ID: G012 Proposer: Crenshaw Institution: Georgia State University Proposal Title: Variable Absorption in the Seyfert Galaxy NGC 3516 The most popular models for the intrinsic UV and X-ray absorption lines in AGN invoke accretion-disk winds that are driven outward by radiation pressure, magnetocentrifugal forces, andor thermal pressure. However, recent observational evidence suggests that most of the UV absorption in Seyfert galaxies arises from much further out than predicted by these models, at distances of tens of parsecs (in the inner narrow-line region). Is there any evidence for absorption close to the nucleus, providing at least indirect evidence for accretion-disk winds NGC 3516, with high-column UV and X-ray absorbers at distances less than 0.2 pc from its active nucleus, is a prime candidate for detecting accretion-disk outflows, possibly due to a special viewing angle with respect to its accretion-disk axis. We propose new FUSE observations of NGC 3516 over a range of time scales days to months) much smaller than previously obtained (years) to pin down the distances, dynamics, and physical conditions of its UV absorbers, and thereby test the accretion-disk wind scenario. NGC 3516 provides multiple opportunities to obtain four 20 ksec CVZ observations over a range of time scales during Cycle 7. Prop ID: G013 Proposer: Iping Institution: Catholic University of America Proposal Title: Probing the Halo and ISM of Low-Redshift Galaxies with Young Supernovae We propose a Target of Opportunity program to study the halo and ISM of a low-redshift galaxy hosting a bright new supernova (V lesssim 3). The primary objectives are to characterize the ionization state, gas-phase abundances, metallicity, and gas kinematics in the ISM and halo of the host galaxy, and, if the properties of the sightline are favorable, in the intervening intergalactic medium. Core-collapse supernovae occuring in nearby galaxies are the potential targets for this program. The FUSE spectral range provides a comprehensive set of lines to study the hot, warm, and cool phases of the ISM. Core-collapse supernovae, primarily SN type II, have strong, nearly featureless UV continua that provide outstanding opportunities to obtain high-quality absorption line spectra of the gas on the line of sight to the SN. Our team has the experience and extensive ground-based support to promptly assess the suitability for this program of each newly-discovered supernova. Prop ID: G014 Proposer: Hebrard Institution: Institut dAstrophysique de Paris Proposal Title: Surveying the sight lines of subdwarfs beyond the Local Bubble Deuterium abundance measurements allow constraints to be put on the Big Bang Nucleosynthesis, the baryonic content of the Universe, and the chemical evolution of galaxies. Such measurements in a variety of astrophysical environments was one of the main justifications for FUSE. This program is dedicated to the interstellar deuterium abundance, representative of the Present Epoch, noted DH_PE. The first FUSE results show that DH_ISM likely has a single value in the Local Bubble, near 1.5times10^-5. Beyond 100pc, however, analyses of more than 10 sight lines show a range of DH values that disagree with the local value. Two interpretations are proposed. One assumes deuterium is depleted onto dust grains and finds DH_PE above 2times10^ -5 . The second emphasizes the DO measurements and finds dshpe below 1times10^: -5 . Both would challenge models of deuterium evolution. Definitive conclusions are prevented by the limited number of measurements. We propose here to increase the sample of deuterium measurements along distant sight lines. Subdwarfs are targets that are especially well adapted for this purpose. This survey program will allow deuterium abundances to be measured toward new distant sight lines, as well as extra candidates for deuterium measurements outside the Local Bubble to be selected for futureobservations. Prop ID: G015 Proposer: Redfield Institution: McDonald Observatory, University of Texas Proposal Title: Variations in the Ionization Structure within the Local Interstellar Cloud and Neighboring Clouds We propose to observe six nearby high latitude stars to measure the variation in ionization structure within the Local Interstellar Cloud LIC) and other neighboring clouds. Of particular interest are the first three ionization stages of carbon and nitrogen, which are controlled by the (partially shielded) interstellar radiation field. FUSE is the optimal instrument for this kind of study because only FUSE can access the resonance lines of CIII (977.020AA), NII 1083.99AA), and NIII (989.789AA). Since all of our targets have high resolution STIS or GHRS spectra, the velocity structure of all components are well characterized. With both the HST and FUSE spectra, we can measure column densities of several ions, including CI FUSE and HST), CII (FUSE and HST), CIII (FUSE), NI (FUSE and HST), NII (FUSE), and NIII (FUSE), sampling many important ionization stages. These observations will detect differences in the ionization structure within the LIC and other nearby clouds, and we will test whether these differences can be explained by different amounts of hydrogen continuum shielding of photoionizing radiation from bright sources like betaCen. The ionization structure of the Local Interstellar Medium (LISM) is vital to understanding the formation, energy balance, and evolution of the LISM. Prop ID: G016 Proposer: Rauch Institution: Eberhard-Karls-Universitat Proposal Title: On the Evolutionary Status of Extremely Hot Helium Stars - are O(He) Stars Successors of RCrB Stars? 95% of all stars end their lives as white dwarfs. About 20% of the hot post-AGB stars are hydrogen deficient. Most of these are the result of a late helium-shell flash, but the evolutionary status of a fraction of about 10-20 O(He) stars, is as yet unexplained. They could be the long-sought hot successors of RCrB stars, which have not been identified up to now. If this turns out to be true, then a third post-AGB evolutionary sequence is revealed, which is probably the result of a double degenerate merging process. More generally, understanding details of merging double degenerate stars is of interest in the context of SN Ia events and hence cosmology. Prop ID: G017 Proposer: Jenkins Institution: Princeton University Proposal Title: Why is Some Neutral Hydrogen in Interstellar Atomic Clouds so Extraordinarily Cold We propose to observe 2 stars behind a complex of unusually cold HI clouds that produce shadows in the background 21-cm line radiation. These clouds are not the classical dense molecular clouds that are known for their strong CO line emission. Our objective is to learn how this material arrives at temperatures well below those given by standard theoretical predictions. By measuring the ortho-to-para ratio of H_2, which equilibrates very slowly with the local kinetic temperature, we can determine if the gas has been cold for a long time, as one might expect if the clouds are stable and heating rate is abnormally low, or, alternatively, if the coldness is a very temporary condition brought about by rapid responses to turbulent expansions and compressions. In addition to using FUSE to measure the abundances and rotational excitations of H_2 and CO, we plan to compare the gas-phase abundances of Fe and O, so that we can test the proposition that there might be a deficiency of grains that emit energetic photoelectrons that would normally heat cold clouds. Prop ID: G018 Proposer: Knauth Institution: Northwestern University Proposal Title: The Enigma of the Interstellar N_2 Abundance N_2 is the most abundant molecule in environments as diverse as the atmospheres of Earth and Titan. Yet, until recently, little was known about its abundance in the ISM since the only accessible N_2 transitions lie in the far-UV. Utilizing the high-sensitivity of the FUSE detectors, Knauth and collaborators reported on the first detections of interstellar N_2 toward the stars HD124314 and 20Aql. The observed N_2 fractional abundances are almost two orders of magnitude larger than expected from models of interstellar nitrogen chemistry for diffuse clouds and do not agree with predictions from dark cloud chemistry either. Here, we propose high SN (30), SiC only, FP-SPLIT observations toward four carefully chosen moderately-reddened stars which have substantial amounts of interstellar CO (spanning almost two orders of magnitude in column density). The N_2 detection threshold N(N_2) > 6x10^12 cm^-2 is a factor of five more sensitive than previous measurements. Our proposed observations will set stringent limits on the N_2 abundance along sightlines with substantial amounts of molecular material and provide clues toward either new N_2 production routes or for modification of the poorly known production andor destruction reaction rates. Prop ID: G019 Proposer: Knauth Institution: Northwestern University Proposal Title: The Interstellar NO Ratio - Evidence for Local Infall Sophisticated nucleosynthesis models exploring the infall of low-metallicity high-velocity clouds on the chemical evolution of the host galaxy can account for the observed NO variations in metal-poor and metal-rich external galaxies. Subtle variations of the interstellar Osmall I abundance in the Solar neighborhood suggest that infall of low-metallicity gas may have occurred within the Solar neighborhood. Precise observations of the NO abundance ratio are essential to test this hypothesis. Recent FUSE measurements of NH_tot reveal variations with N(H_tot), but with significant scatter due to observational uncertainties. Here, we propose to obtain additional high SN observations of the weak interstellar Nsmall I doublet at 160AA in order to derive accurate nitrogen abundances and provide a direct comparison with the existing data. All stars in our sample have high-precision STISHST measurements of the weak Osmall I 356AA line for a variety of stellar distances (0.2 leq d leq .5 kpc) from the Sun. This proposal is designed to investigate an intriguing trend with distance detected in the best published NO data available. If verified, these NO variations provide direct evidence for different nucleosynthetic histories within and around the Solar neighborhood. Prop ID: G020 Proposer: Bowen Institution: Princeton University Proposal Title: A Search for Hot Baryons in the Halos of Nearby Galaxies We propose searching for OVI (and Lyman beta) absorption lines from the halos (simeq 8-280h radii) of five nearby galaxies, using background QSOs or AGN as probes. The detection of OVI around galaxies is likely to have important implications for our derstanding of how galaxies form and evolve. Models predict that gas creting to galaxies from the formation of galactic large scale structure (or om, g., the assimilation of dwarf satellites) should be shock-heated to mperatures at which oxygen would be detectable as OVI. At the same me, galaxies should also be feeding hot gas back into the intergalactic medium via winds driven by supernovae. Some of these processes may well be responsible for the High Velocity Cloud complexes seen in the Milky Way. Despite the importance of such mechanisms, however, we have very little direct evidence of how hot, metal-enriched gas behaves close to a galaxy, or even that it exists beyond a few kpc. With this proposal, we seek to search the halos of various types of galaxies for OVI-absorbing gas, using the few probes which are bright enough to be observed by FUSE and which are at declinations above 50 deg. Although the number of galaxies probed will be small, our observations will provide a first estimate of how far OVI extends from a galaxy, its covering fraction, whether the column density declines with distance, and whether the absorption complexes show unusual velocity structure, as might be expected from the more dynamical processes such as galactic outflows. Prop ID: G021 Proposer: Skillman Institution: University of Minnesota Proposal Title: The True Chemical Abundances of Dwarf Galaxies FUSE has discovered a putative offset between the neutral and ionized gas phase chemical abundances of nearby dwarf starburst galaxies. This important and intriguing result is in the sense that the neutral gas phase abundances are significantly (approx 1 dex) lower than the HII region abundances. Thus, the starburst environment may be surrounded by a lower metallicity halo. This could be a result of either chemical pollution of the medium closely surrounding the starburst or a metallicity gradient from the inner (relatively) metal rich galaxy to an outer metal poor halo. This potentially high impact result is not yet secure because the neutral gas absorption lines may yield underestimates of the abundances due to ionization, depletion, andor saturation effects affecting the various chemical elements. For several reasons, oxygen is the ideal element to concentrate on, and by observing multiple OI lines with different oscillator strengths - and thereby addressing saturation concerns - we can obtain a secure absorption line oxygen abundance for the neutral gas phase for the first time. A deep FUSE integration of a carefully selected and previously observed target (NGC3353 equiv Haro3 equiv Mrk35) will allow us to measure neutral oxygen lines over a range in oscillator strength, and thus support or question this very important FUSE discovery. Prop ID: G022 Proposer: Blair Institution: Johns Hopkins University Proposal Title: FUSE Survey of Magellanic Cloud Supernova Remnants Continued We propose to continue an unbiased ultraviolet survey of supernova remnants in both Magellanic Clouds that was begun in FUSE Cycles 4 and . In these earlier programs, we have successfully detected at least 5 Magellanic remnants, 14 of which had no previous FUV observations. This work indicates that optical andor X-ray characteristics of supernova remnants are not always good predictors of the objects that will be bright and detectable in the UV. This survey proposal will add to this unique database by obtaining spectra of additional Magellanic Cloud remnants with a range of radio, optical, and X-ray properties. A standard request of 10 ks per object using the LWRS aperture is used for the survey, reaching a limiting flux in OVI lambda 1032 about a factor of 100 below the flux observed for the bright LMC remnant N49. In this proposal, we request time to observe any or all of the previously proposed targets that have not yet been observed (10 SMC objects plus 1 LMC object), and 11 new LMC remnants identified only recently as part of the MCELS project. As a survey program, the time and number of targets listed is effectively an upper limit to the actual request. Prop ID: G023 Proposer: Ayres Institution: University of Colorado (CASA) Proposal Title: High-Declination Late-Type Supergiants in the Mass Range 5-7 Suns Late-type supergiants represent the terminal evolutionary stage of short-lived high-mass stars. We shouldnt expect their coronal magnetic behavior to be anything like the long-lived low-mass Sun. Many GK supergiants fulfill that expectation by displaying prominent cool wind absorptions in Mg II, and little if any coronal X-ray emission. Yet, a number of early-G supergiants do exhibit symptoms of solar-type coronal behavior, down to details like redshifted transition zone (T 10^5K) emission lines. Even among these active supergiants, however, L_XL_CIV ratios curiously are depressed an order of magnitude below solar-like stars. The winds of the inactive supergiants, and the X-ray deficiency of the active class, are important issues in stellar high-energy astrophysics; where the diagnostic power of FUSE spectroscopy can be put to good use. We propose to add to the mix two key late-type supergiants---Beta Cam G0Ib) and Beta Ind (K1II)---not previously observed by FUSE; and a new pointing on the archetype hybrid chromosphere star Alpha TrA K2II), recorded by FUSE in 00 and 02, but now a planned target (as is Beta Ind) for an upcoming joint ChandraHST imaging program. vskip 0mm Prop ID: G024 Proposer: Friedman Institution: Space Telescope Science Institute Proposal Title: Probing Small-Scale ISM Variations with Multi-Epoch FUSE Observations The existence of small scale structures in the interstellar medium ISM) has now been verified using a variety of techniques, including optical, radio, and ultraviolet instruments. They have been observed on scales ranging from tens of AU to parsecs. One of the best ways to probe the smallest scales is with multi-epoch observations, in which one discerns spectral changes arising from material between an observer and a background source. The number of such observations in dominant species in the ISM, as revealed by absorption line studies in the ultraviolet, is very small. In addition, the physics of these structures, including their confinement mechanisms, lifetimes, pressures, and composition, is not well-understood. We propose a survey program to re-observe 18 stars already observed with FUSE more than 3 years earlier to search for time dependent changes in their spectra. We will do profile fitting, curve-of-growth, and apparent optical depth analyses to search for changes in H2 and a variety of other species, such as CI, FeII, PII, ClI, and ClII. These will allow estimates of electron temperatures, volume densities, and depletions. The stars were selected on the basis of early spectral type, and existing high SN FUSE spectra obtained in TTAG mode, which will allow the best opportunity to detect subtle changes in the spectral features. The newly obtained data will be useful for a variety of investigations beyond those described here, by providing a dataset of multi-epoch, high SN spectra of early-type stars. Prop ID: G025 Proposer: Iping Institution: Catholic University of America Proposal Title: FUV Study of the Extreme Wolf-Rayet Binary CQ Cephei We propose a series of FUSE observations of the Wolf-Rayet + O star binary CQ Cephei to determine the structure of the bow shock zone formed when the winds of the two hot stars collide. CQ Cephei has the shortest period of all the known WR+O binaries and would be the first WN+O binary to be studied in this way by FUSE. Analysis of the FUSE spectra will lead to improved constraints on orbital parameters and on characteristics of the WR star itself (wind momentum, mass-loss rate, and abundances). Of particular importance in the FUSE wavelength range is the large number of emission lines with different ionization potentials from abundant elements, ranging from OVI, S IV, P V, C III, to N II. The S and P lines are important because these elements are produced only in SN explosions and are not enhanced by CNO processes. The proposed observations will cover a significant part of the .64-day orbital period to map the wind interaction zone from phase-dependent spectral variations. Prop ID: G026 Proposer: Iping Institution: Catholic University of America Proposal Title: Mass Loss Processes in Luminous Blue Variables and Late-Type Wolf-Rayet Stars We propose a FUV survey of evolved massive stars in the Galaxy, LMC, and SMC. The targets include Luminous Blue Variables (LBVs) and late-type Wolf-Rayet (W-R) stars. LBVs, a transition stage between O and W-R stars, are in the early stages of post-main sequence evolution. They undergo brief, high mass-loss-rate episodes that bring processed material from deep within the stars to the surface. The far-UV spectra will be used to determine stellar wind mass-loss rates and terminal velocities at different metallicities. The role of rotation, asphericity and clumping in the wind will also be investigated. Spectral features tracing a range of wind ionization states will be modelled with the latest version of the non-LTE, line blanketed, geometrically extended, expanding atmosphere code CMFGEN. The FUSE spectral range is ideally suited to test these models and determine metallicity effects connected with the complex mass loss from LBVs and W-R stars. Prop ID: G027 Proposer: Giroux Institution: East Tennessee State University Proposal Title: An Abundance Study of the Magellanic Stream We propose FUSE observations of the Seyfert Galaxy Fairall 9. This sightline probes the Magellanic Stream, the most prominent example of the class of high velocity clouds (HVCs). While the origins of the HVCs in general are still unclear, progress in the understanding of the Magellanic Stream has been made possible by the SII abundance measurements and SiII limits made using Hubble Space Telescope (HST) spectra of Fairall 9 (Gibson, Giroux, et al. 2000). Preliminary FUSE observations toward Fairall 9 have also been used to characterize the H_2 abundances in the Magellanic Stream, as well as detect the presence of collisionally ionized gas in the form of OVI. Extended observations in the FUSE band, however, promise to open up transitions of the dominant ionization stages of N, O, Si, Fe, Ar, and P in the neutral phase of the Stream. This will allow both measurement of the metallicity of the Magellanic Stream and an estimate of the relative abundances of these elements. This information will allow an initial assessment of the depletion of refractory elements as well as the nucleosynthetic history and possibly the dynamic history of the gas. Further, this observation will permit a detailed study of a multiphase region associated with the Stream, whose properties can be compared with regions associated with sightlines through the Galactic Halo. Such tidally-stripped gas may also be a local example of multi-phase absorbers in the intergalactic medium. Prop ID: G028 Proposer: Korpela Institution: University of California Proposal Title: Atomic and molecular gas toward the north ecliptic pole SPEAR observations of the North Ecliptic Pole (Korpela, 2005) have resulted in a number of detections of atomic emission and molecular fluorescence lines, including a possible detection of fluorescent emission from molecular nitrogen. It is difficult to reconcile some of these emission feature with collisional processes at the abundances thought to be typical of the ISM. We will use two short-duration absorption observations of early type stars, one of a star with low reddening (E(B-V)0.04), one with higher reddening (E(B-V)0.5) to confirm line identifications and constrain our models of the emission seen by SPEAR. Prop ID: G029 Proposer: Leighly Institution: The University of Oklahoma Proposal Title: Tropical Storm to Hurricane The Emergence of a BAL Wind We propose a 60 ks FUSE observation to quantify the outflow properties of the unusual Narrow-line Seyfert 1 Galaxy WPVS007. Observed to have a miniBAL with maximum velocity v_max sim 1000 , km, s^-1 in an HST observation from 1996, it was discovered to have developed an additional BAL flow by the time of the FUSE observation seven years later. The BAL flow has a maximum velocity of at least ,000 , km, s^: -1 , and the unambiguous presence of ion P 5 indicates that it is very optically thick. In addition, it was found to have normal X-ray flux during the ROSAT All Sky Survey, but in subsequent observations from 1993 to 2003 it was observed to be X-ray weak, suggesting that the X-rays were absorbed by the emerging BAL. This observation is remarkable, because the emergence of a BAL flow has never been observed before. Furthermore, the observation of a BAL flow in such a low luminosity object (M_V-19.7) is unprecedented. We propose another FUSE observation to look for further variability and development of the BAL flow. We will study the ionP5 lines which may not be saturated and therefore may be sensitive to changes in the BAL flow. We expect that these observations will place strong constraints on the kinematics, energetics, and physical conditions of BAL outflows, as well constraints on the geometry and stability of the outflows. Prop ID: G030 Proposer: Dupke Institution: University of Michigan Proposal Title: The North Ecliptic Pole Supercluster A Window to Detect the Local Missing Baryons Simulations predict that nearly half of the baryons in the local universe are in a moderately hot phase, 10^5-10^7 K, largely in the form of giant cosmic filaments that connect the denser virialized clusters of galaxies. Since they are tenuous and have low overdensities these missing baryons evade detectability and are missing from census of the baryonic content of the local universe. They, however, can be detected through absorption lines they produce in the spectra of background AGNs. The highest covering fraction of such filaments occurs in superclusters and an initial study of AGNs projected behind superclusters has shown absorption systems (in LyalphaLybetaOVI) at the supercluster redshifts. Here we propose to build upon our initial successful detections and expand our sample by nearly 50 discovered in the ROSAT North Ecliptic Pole survey. This is best known supercluster to study the Cosmic Web because it is entirely selected in X-rays, which defines the real potential well best, but also has the largest number of bright background AGNs, among all cataloged superclusters. Furthermore, it matches very well the current observational contraints of FUSE, which is, with the demise of STIS, the only satellite that is able to detect the key absorption lines for this study. Prop ID: G031 Proposer: Irwin Institution: University of Michigan Proposal Title: Can FUSE Tell Us if Intermediate Mass Black Holes Exist Ultraluminous X-ray sources (ULXs) are the brightest non-nuclear X-ray point sources in galaxies, and are second only to AGNs in bolometric luminosity. However, despite a concerted effort in the last few years to determine the nature of these enigmatic objects, it is still unclear exactly what they are. If they are accreting 10 M_odot black holes X-ray binaries like those found in our own Galaxy, then they are emitting at luminosities approaching 100 times their Eddington luminosity (most probably through beaming of the X-ray emission). Alternatively, it has been suggested that these ULXs harbor intermediate mass black holes with masses 100--10000 M_odot, whose exist would bridge the gap between normal stellar-mass black holes and supermassive black holes. At the same time, the existence of intermediate mass black holes would challenge our notions of how black holes form. The expected flux and velocity structure of OVI emission from the accretion disk of the black hole could provide an important diagnostic for distinguishing between beaming and intermediate mass black hole scenarios. We propose the first far-ultraviolet observation of any ULX, a 70 ksec observation of a ULX in Holmberg II as a test case for using OVI emission as an indicator of the presence of intermediate mass black holes within ULXs. Prop ID: G032 Proposer: Brown Institution: University of Colorado Proposal Title: Magnetic Fields on Alien Dwarfs -- Stellar Activity in the Arcturus MG The Arcturus Moving Group is very likely a remnant of the merger of a dwarf galaxy with the Milky Way Galaxy in the distant (7- 8 Gyr) past. This kinematically distinct group has members that are located very close to the Sun, allowing study of stellar magnetic activity on very old stars that typically would not be possible. We propose to use FUSE spectra to study three dwarf members of the Arcturus Moving Group with the aim of determining their transition region (UV emission line) activity levels, and the effects of low metallicity on the transition region radiative losses. Our targets have metallicities of 20 spectral types G1 - K0, and are at distances less than 35 pc from the Sun. Our aim is to measure fluxes for the O VI 1032, 1038AA and C III 77, 1175AA emission lines, which are excellent diagnostics of the radiative losses from 0.5 - 3 10^5 K plasma. The measured optical chromospheric Ca II emission levels of the targets are comparable to or higher than that of the quiet Sun. Prop ID: G033 Proposer: Bianchi Institution: Johns Hopkins University Proposal Title: The UV-brightest Milky Way hot stars detected by GALEX We propose to observe with FUSE the hottest, UV-brightest stellar objects selected from the UV sky surveys produced by GALEX and overlapping with the SDSS optical survey. We analyzed a total of 744 GALEX fields with a unique overlapping area to the SDSS of over 400 square degrees. We classified the UV sources, and estimated their physical parameters, by comparing their multi-band photometry (two GALEX bands, FUV and NUV, and five SDSS optical bands (u, g, r, i, z) to model colors Bianchi et al. 2005a, b). The number density of some classes of astrophysical objects is increased by factors up to 100 with respect to previous catalogs, in particular very hot stars such as white dwarfs (single and in binaries). We selected the 20 UV-brightest hot objects from the fields at the high declinations accessible by FUSE. FUSE spectra, with GALEX and optical follow-up spectra already available or under way, will uniquely enable us to accurately model the atmospheres and winds (when present) of these hot stars, extending the -so far very limited - detailed measurements of stellar parameters, that led to a number of important results such as a revised Teff - spectral type calibration for pop-I O stars e.g. Garcia and Bianchi 2004), and the discovery of highly ionized neon in post-ABG objects, a crucial diagnostic for very hot stars with weak winds (Herald et al. 2005). Determing neon abundances in WD stages where the winds are fading is an important diagnostic for stellar evolution. The proposed sample will also significantly augment the potential of the FUSE archive with new high Galactic latitude sight lines for ISM studies, and provide an unprecedented FUSE-GALEX legacy data-base of UV-selected MW objects. Prop ID: G034 Proposer: Bianchi Institution: The Johns Hopkins University Proposal Title: Far-UV extinction by dust in unexplored LMC environments We propose to study the far-UV extinction in selected sightlines in the LMC, sampling three environments with differing levels of star formation activity, including the general field, hitherto unexplored. Extinction properties in the far-UV will give information about the distribution of small dust grains. The investigation is important to understand the role of dust in the star formation and ISM enrichment history of galaxies, and the relations of extinction to global galaxy properties such as metallicity and starburst intensity. It will be ultimately useful to interpret integrated properties of distant galaxies, such as those measured by the GALEX UV surveys. We will derive extinction curves using pairs of stars in the LMC. Studies of extinction in the UV range (> 1200AA) indicate a complex dependence of the dust properties with environment, where metallicity and starburst activity are relevant factors. Therefore, we have chosen pairs of stars inside, and far from, bright OB associations, to explore relations of dust properties with environment. acquired complementary HST STIS and ACS spectra (1200-3200AA) of the proposed targets (HST cycle 12 GO9827). properties The combined HST (UV) and FUSE (far-UV) results will provide a unique opportunity to study the properties of small grains. Prop ID: G035 Proposer: Gaetz Institution: Smithsonian Astrophysical Observatory Proposal Title: Dynamics of a Young, O-Rich Supernova Remnant in the Small Magellanic Cloud The supernova remnant 1E0102.2-7219 in the Small Magellanic Cloud is the best studied O-rich remnant after Cas-A, having been observed in bands from radio through X-ray. In spite of its simple appearance round remnant, bright reverse shock) the remnants structure is complex. X-ray kinematics suggest an expanding toroid viewed nearly on-axis, while optical kinematics suggest an expanding shell with a bubbly internal structure. We will use FUSE to examine the velocity structure on sight-lines through the center of the remnant which will complement our Cycle 3 observations of the bright X-ray ring. These observations will provide OVI kinematic data for comparison to the optical OIIIf and X-ray grating kinematic data. The MDRS slit samples a significant fraction of the projected area, but is small enough to isolate interesting structure. Recent OIIIf proper motion data yield an expansion center near the X-ray knot in a central X-ray filament, and the kinematic center is included in all the proposed observations. This will allow a search for evidence (such as variability) for a compact central object which should have been produced by the collapse of a massive star. Prop ID: G036 Proposer: Moffat Institution: Universite de Montreal Proposal Title: Does Metallicity Affect Clumping in Hot-Star Winds All hot, luminous stars drive strong winds, that have a major impact on their evolution and their surroundings. This was especially important in the early Universe, that was dominated by massive stars with very low metallicity. But what were the actual mass-loss rates then Small-scale structures (clumps) are considered as the main factor which can reduce the observed mass-loss rate, by a factor of at least 3. No one knows whether and how clumping changes with the decreasing fraction of wind-driving metals. We propose to approach this important question by detecting clumps in hot-star winds of 2 selected single WN stars in the SMC, where metallicity is one-tenth solar. Prop ID: G037 Proposer: Pellerin Institution: Space Telescope Science Institute Proposal Title: FUV Spectral Variations of Wolf-Rayet Type Stars The understanding of Wolf-Rayet type stars is fundamental since they are involved in chemical enrichment processes of interstellar and intergalactic medium by releasing a lot of metals produced during the CNO cycle. The FUSE spectral range includes several spectral transitions from highly ionized atoms in the far-ultraviolet range that can improve the understanding of massive star evolution. However, the wavelengths below 1200AA remains a range quite unexplored for these stars. Recent far-ultraviolet spectra from FUSE show, for the first time, strong evidences for important stellar line profiles variations for a given WR subtype, which are not seen at optical wavelengths. These variations may be related to evolutionary stages of Wolf-Rayet stars. Unfortunately, the number of Wolf-Rayet stars observed below 1200AA is actually too small to study and characterize these variations within a spectral class. Using FUSE, we propose to observe additional Wolf-Rayet stars of WN-types to better characterize these spectral variations. A quantitative analysis of these spectra will be performed using the NLTE model atmosphere code CMFGEN. Prop ID: G038 Proposer: Herald Institution: The Johns Hopkins University Proposal Title: Investigating the Neon Abundance of LMC WO stars WO stars represent the most evolved sub-type of Wolf-Rayet class, which are believed to descend from the most massive of the O-stars. WOs are the hottest (T>100,000K) and also the rarest; only seven are known among the Local Group, out of hundreds of known WR stars. Their spectra are characterized by strong oxygen and carbon emission lines, which form in their fast (4000kms) stellar winds. Despite their evolutionary importance, only two of these rare objects have been observed by FUSE; Sanduleak 2, a WO3, and Sanduleak 1, a WO4+O binary. Unfortunately, during the observation of Sanduleak 2, the SiC detector was misaligned, resulting in no useful data for the short wavelengths of the FUSE range. As these stars represent the only WO stars currently observable by FUSE, we request a re-observation of Sanduleak . The SiC detectors cover the wavelength range where the important SVI lambda lambda 933,944 doublet lies, as well as NeVII lambda973. This neon feature has been recently identified in the FUSE spectrum of a rare transitional WO-PG1159 central star of a planetary nebula. If it appears in the spectrum of Sanduleak 2, it may allow the neon abundance, an important evolutionary diagnostic, to be determined for a star in the most advanced WR phase. We shall use stellar atmosphere codes to model the FUSE spectrum of Sanduleak 2 to better determine parameters such as mass-loss rate, stellar temperature, and chemical abundances, allowing a better evolutionary understanding of this rare class of objects and WR stars in general. Prop ID: G039 Proposer: Herald Institution: The Johns Hopkins University Proposal Title: Wolf-Rayet Stars in Environments of Different Metallicity Wolf-Rayet (WR) stars, thought to descend from the most massive stars, are important drivers of galactic evolution through their injection of mechanical energy, chemically enriched material and ionizing photons into their surroundings. They are a key to understanding massive stellar and galactic evolution, as well as nucleosynthesis processes. An important aspect in the understanding of WR stars is the influence of the metallicity of their environment on their parameters and evolution. To shed light on this question, we wish to study and compare two like samples of WR stars from environments of differing metallicity; the Milky Way and Small Magellanic Cloud (SMC). FUSE observations provide crucial diagnostic lines for measuring mass-loss parameters, effective temperatures, and certain abundances. We will model the FUSE spectra to derive the stellar parameters of these objects, which will help answer the following outstanding questions; i) What effect does metallicity have, if any, on the wind properties of WR stars (ii) Do wind clumping parameters (which directly affect derived mass-loss rates) determined from far-UV diagnostics agree with those derived from IR diagnostics (iii) Do observed WR parameters agree with predictions of theoretical evolutionary models (iv) Do observed SMC WR properties agree with those currently adopted in low-metallicity stellar synthesis models (v) Do X-ray parameters derived from stellar atmosphere models agree with observed X-ray fluxes Prop ID: G040 Proposer: Godon Institution: Villanova University Proposal Title: FUSE Survey of DN basic characteristics of the WD and accretion disk The white dwarfs (WDs) in cataclysmic variables (CVs) are probes of cataclysmic evolution and accretion physics because they bear the thermal, chemical and rotational imprint of their long term accretion and thermonuclear history. An understanding of the consequences of accretion in CVs is the first step in a global understanding of accretion-related phenomena throughout the universe including Young Stellar Objects, galactic binaries (accretion onto neutron stars and black holes) and AGN, which cant be easily observed. We propose a FUSE survey of 16 dwarf nova (DN) systems (a class of CVs in which the WD can easily be observed) for which FUV spectra in quiescence have never been obtained before. These systems have not been studied in detail (only five have a known period) and little is known about their accreting WD. We propose to determine the WD surface temperature, gravity, rotation rate and composition and probe their innermost disk accretion flows (e.g. detect and characterize accretion belts) by applying multi-component synthetic spectral analyses to the FUSE data. We will use photometry to look for periodic signals in the FUSE time tag data and determine the orbital period of those systems for which it is unknown. Prop ID: G041 Proposer: Godon Institution: Villanova University Proposal Title: BZ UMa an Intermediate Polar Candidate We propose FUSE observations of the Dwarf Nova (DN) BZ UMa which is a candidate for Intermediate Polar (IP). In quiescence, BZ UMa has an apparently large N,sc vC,sc iv which is atypical of most DNe and its FUV spectrum is dominated by the white dwarf (WD). High frequency QPOs, high excitation lines and strong X-ray emission have been detected suggesting it is an IP. The truncated inner disk helps lower the luminosity and exposes the WD in the FUSE range, therefore allowing us to estimate the temperature of the WD (Teff) and the chemical abundances (to check signs of elevated N and depleted C as well as elevated abundances of odd numbered nuclei from proton capture during CNO burning). Currently, there are only two IPs with known Teff and the present FUSE proposal aims at adding an additional object in order to better understand the accretion geometry and evolutionary history of these systems. Prop ID: G042 Proposer: Godon Institution: Villanova University Proposal Title: FUSE Observation of the eclipsing Dwarf Nova IY UMa IY UMa is a recently-discovered double-lined eclipsing CV with an extremely high inclination. The orientation allows us a view into a narrow shock-heated cavity driven into the disc edge by the accretion stream from the mass donor star. This (literal) probe is so far unique. At the orbital phase when we look into the hot cavity, the emission from the cavity should be a significant fraction of the total UV flux. Comparison with our hydrodynamic simulations of the stream-disc impact will allow us to determine the structure of the cool quiescent outer disc. We will fully characterize the white dwarf, measuring its rotation rate, surface gravity, effective temperature, chemical abundances and accretion rate. The obscuration of the inner UV emitting regions by vertical structure associated with spiral density waves will be measured and interpreted by comparison with our simulations. Prop ID: G043 Proposer: Shull Institution: University of Colorado Proposal Title: Interstellar H_2 near the Lockman Hole We propose to observe 3C263, a bright, high-latitude AGN located at high declination (+65.8 deg) near the Lockman Hole. This sightline is part of an extended region of low H2 column densities identified in our FUSE survey of high-latitude H2 (Gillmon et al. 2006). The regions of low NH2 appear at Galactic latitudes b > 55 deg and extend from 60 deg < l < 180 deg. The Lockman Hole (low NHI) and Northern Galactic Chimney (low N_NaI) are both contained within this extended H2 Hole, identified in 8 AGN sightlines (b > 50 deg) with NH2 < 10^15 cm^-2 in our FUSE survey. The 3C263 sightline probes a low NHI region toward the edge of the Lockman Hole. With this and other data, we will characterize the structure and extent of infalling high-velocity clouds (HVCs) in the Galactic halo and cross-correlate H2 with the presence and strength of OVI, which is also patchy at high latitude. Low-H_2 sightlines may be associated with low NHI and N_NaI and with IR cirrus emission (Gillmon & Shull 006). At SN > 6 per resolution element, our spectra will be sensitive to log NH2 > 14.0 with line-stacking of several Lyman bands. High-latitude sightlines with low NH2 are also valuable for studies of the IGM, owing to their low H2 line contamination. Together with previous high-latitude, low-NH2 sightlines, our target will better define the H2 and Lockman hole, the mass of high-latitude H2, and the relation of this gas to the distributions of HI, OVI, infrared cirrus, and other large-scale Galactic halo structures. Models of H2 rotational excitation will be used to derive the gas temperature, density n_H, and UV radiation field and at high Galactic latitude, in a new regime of optically-thin, low-NH2 gas inaccessible to FUSE in the Galactic disk. Prop ID: G044 Proposer: Shull Institution: University of Colorado Proposal Title: Detecting the Elusive Hot Baryons in OVI One of the important discoveries of FUSE and HST was the detection of intergalactic OVI absorbers, possibly associated with the warm-hot intergalactic medium (WHIM) at 10^(5-6)K. Danforth & Shull (2005) found 40 OVI absorbers in 31 sightlines, spanning Delta z approx 2.2, and estimated that 5-10 gas. With a steep column-density distribution calN (N_OVI) proportional to N_OVI^-2.2 pm 0.1, weak absorbers contain much of the total mass. Thus, it is important to measure OVI absorbers down to weak levels (Nosix approx 10^13 cd) in order to (1) obtain an accurate baryon census of the hot IGM; (2) test the predictions of cosmological simulations for WHIM redshift evolution; (3) probe the distribution of IGM metals; (4) compare the metallicities with the large-scale distribution of galaxies. We propose to observe 6 high-declination AGN to probe OVI, CIII, and HI absorbers. Danforth & Shull (2005) estimated that 5--10 OVI-bearing gas, and they estimated the metallicity at sim0.1 solar. Previous OVI surveys are highly incomplete in these weak absorbers W_lambda < 80mAA) that contain a significant fraction of WHIM baryons. We will also measure HI Lyman beta and CIII lambda 977 to improve the multi-phase baryon census at z < 0.15. FUSE and HST archival OVI data will be compared to test simulation predictions that the WHIM mass fraction increases at lower redshifts. Galaxy redshift surveys will allow us to study the connections between OVI absorbers and the large-scale filamentary structure of galaxies, complete down to approx 0.2L^* at low redshifts, z < 0.15. We will use the combined absorber and galaxy data to estimate the extent of metal dissemination in the IGM. Prop ID: G045 Proposer: Cheng Institution: California State University, Fullerton Proposal Title: Circumstellar Absorption Lines in the Far-UV Spectra of Ae and A-Shell Stars A-shell stars are characterized by the coexistence of two types of line profiles in their spectra, one originating in the stellar photosphere and the other originating in the cooler shell. These stars are of great interest because shell characteristics appear in three important types of A stars (1) Those with infrared excess arising from circumstellar dust (Vega-like objects), (2) beta Pic-like objects, and 2) lambda Bootis stars (metal-deficient A stars with infrared excess). Snow et al. (1979) used Copernicus data to study 17 Be and B-shell stars, which have a rich shell absorption spectrum between 120 and 1140 AA. We propose to carry out a similar far-ultraviolet study of the slightly cooler Ae and A-shell stars. Among the 14 bright Ae and A-shell stars observed in the visual and the near infrared by Jaschek and Andrillat (1998), only 2 stars (HD 103287 and HD 112028) can be observed with FUSE during cycle 7 due to the new pointing constraints. Our new FUSE data will add important information to our previous FUSE studies (cycle 2, 4, and 5) of protoplanetaryplanetary debris disks. Prop ID: G047 Proposer: Blake Institution: MC California Institute of Technology Proposal Title: Evaluating the UV Energy Distribution of the Nearby T Tauri Star T Cha The UV and X-ray energy distribution generated by a young pre-main-sequence (PMS) star can have a profound effect on the excitation conditions in its circumstellar environment. High energy photons can play an important role in photoexciting molecules and dust grains in both the accretion disk and the lower density circumstellar gas. We propose FUSE spectroscopy of the nearby (66 pc), G8, PMS star T Cha, which has not been successfully observed in the UV previously. UV spectra provide vital information on the stength of the high temperature UV emission lines that are a dominant feature of PMS stellar spectra. This star shows an IR energy distribution that suggests that transiently heated (most likely by UV photons) dust may be present. We intend to use the measured O VI and C III emission line fluxesprofiles to estimate the likely overall UV spectrum and to model the photo-excitation effects of this spectrum on the circumstellar gas and dust. Prop ID: G048 Proposer: Dupree Institution: Smithsonian Astrophysical Observatory Proposal Title: A Test of Wind Dynamics in Accreting Young Stars Young stars can not only undergo accretion but also drive fast hot winds. The winds revealed by FUSE spectra in 2 T Tauri stars (TW Hya and T Tau) viewed pole-on can affect the evolution of angular momentum in a system, define the geometry of the stellar magnetic field, cause ablation of a surrounding accretion disk, and serve as an acceleration site for optical jets. We propose to determine the configuration and characteristics of the fast wind with FUSE spectra of 2 edge-on T Tauri stars in the nearby Eta Cha cluster (RECX-11 and ECHA J0843.3-7905) that are well-matched in age to TW Hya. If the outflow is collimated from the stellar polar region, the shape of the O VI and C III lines in high inclination systems should differ markedly from those in systems viewed pole-on. Additionally, signatures of H_2 can indicate its presence (or not) in the circumstellar environment. Prop ID: G049 Proposer: Aracil Institution: University of Massachusetts Proposal Title: The Large-Scale Distribution and Physical Properties of Gas in the Cosmic Web Hydrodynamic simulations of large-scale structure growth predict that at low redshifts, low-density shock-heated gas at T 10^5 - 10^7 K should be distributed in large-scale gaseous filaments that are correlated with the filaments observed in the galaxy distribution, the so-called cosmic web. To test this fundamental prediction of the cosmological simulations, we propose to study OVI, HI, and ancillary absorption lines in the spectra of QSOsAGNs that penetrate large-scale galaxy filaments revealed by the 2MASS survey. Our target 3C204) is well beyond the redshifts of the 2MASS galaxy structures. We will combine the new observation of 3C204 with high quality sight lines already observed with FUSE and HST. Very few existing observations probe the highest density regions in the 2MASS survey, and the proposal observation will bolster the statistics for these crucial regions. We will be able to statistically address the following questions- (1) Does the distribution of gas track the galaxy distribution in the filaments (2) What are the physical conditions of gas inside the filaments, and how do these compare to gas on sight lines through low-density regions and voids Is the gas predominantly collisionally ionized and hot, or is it photoionized and cold Does this depend on environment as expected (3) What is the metallicity of the gas in these different environments (4) How do the observed properties of the absorption lines compare to the properties predicted by the simulations such as the clustering of the lines Prop ID: G050 Proposer: Howk Institution: University of Notre Dame Proposal Title: Far-Ultraviolet Study of the Magellanic Bridge Galaxies are known to interact with each other. These interactions can have profound effects on the gaseous components of galaxies, often by inducing star formation or stripping material from the main bodies of the interacting systems. Thus, these interactions have a significant connection to the manner in which galaxies evolve with time and pollute the intergalactic medium with non-primordial material. The Magellanic Bridge, gas that links the Small and Large Magellanic Clouds (SMC, LMC), is believed to result from a recent close encounter between the SMC and LMC. The Bridge provides an unique opportunity to study tidally-stripped, star-forming gas inasmuch as its proximity to our own Galaxy and the absence of sight line confusion with material from the Milky Way allow us to study it using UV absorption lines. We propose to obtain new FUSE spectra of ESO31-8, a Seyfert galaxy situated behind the Bridge near the SMC, and DGIK975, a B2V star within the Bridge near the LMC. Our observations will provide absolute interstellar Magellanic Bridge abundances. These abundances will be compared to those of the SMC and LMC to determine the origins of the Bridge and the source of its chemical enrichment. We will study and compare the kinematics and column densities of FUV absorptions such as OVI, CIII, SIII, FeIII, PII, SiII, FeII, ArI, and H_2, between several lines of sight within the Bridge and with sightlines within the Clouds to further understand the interaction and evolution of the Magellanic system. Prop ID: G051 Proposer: Howk Institution: University of Notre Dame Proposal Title: Tidal Debris and Halos about the Magellanic Clouds The Large and Small Magellanic Clouds represent the closest gas-rich galaxies to our own Milky Way. The feedback of energy and matter from massive stars has created gaseous halos about these galaxies, as revealed by FUSE observations of OVI in both Clouds. At the same time, the gravitational interactions between the Clouds have stripped gas from their outer regions to form the Magellanic Stream and other prominent gaseous features of the southern hemisphere. Tidally-stripped material such as this may plan an important role in the evolution of galaxies. We propose to observe two UV bright AGNs behind the periphery of the Magellanic Clouds in order to study gas in the far reaches of these galaxies. These objects are drawn from our Cycle 4 survey to identify UV bright objects behind the Clouds. Our proposed observations will allow us to 1) study the hot gas content of the very extended coronae and tidal material of the Clouds through the OVI absorption doublet; ) study the relative abundances and metallicity of gas in the distant reaches of these galaxies; and 3) compare the physical conditions and the large-scale energy content of this distant gas with sight lines within the Clouds. We will compare the absorption properties of the gas in the outer reaches of these low-redshift, low-mass, low-metallicity galaxies with the low-redshift quasar absorption line systems. Prop ID: G052 Proposer: Sankrit Institution: Johns Hopkins University Proposal Title: OVI Emission from Conductive Interfaces in the Local Interstellar Medium We propose observations of OVI emission from conductive interfaces in the local interstellar medium. These interfaces have been identified by their OVI absorption lines in the spectra of nearby white dwarfs. The OVI column densities in the interfaces have been measured. We will target regions at small angular separations from the white dwarfs to ensure that the emission and absorption sample the same gas. The target sight lines were chosen to have high background interstellar extinction, so the probability of contamination by emission from regions further away is minimized. The combination of emission and absorption data for OVI will allow us to obtain the densities of the emitting regions, and the path length through them. This detailed characterization of the interfaces between hot and warmcool gas will allow a greater understanding of the physical processes at work in creating and maintaining them. Our understanding of OVI production in the local interstellar medium can then be applied to the general case, since such interfaces are likely to be ubiquitous in the Galaxy and beyond. Prop ID: G053 Proposer: Danforth Institution: University of Colorado at Boulder Proposal Title: OVI and CIII Emission from LMC Superbubble N70 Superbubbles are a major mechanism of feedback between massive stars and the ISM and are thought to be the primary means through which coronal gas flows from the disk into the halo. Many are seen to be bright in soft X-rays and photoionized optical emission. Between these two phases should exist a warm-hot (T 10^5 K) component formed either through shock heating or thermal conduction. OVI lambda lambda 032,1037 is an ideal tracer of this warm-hot gas as it is not formed through photoionization in the ISM. However, absorption from the diffuse OVI in the LMC halo tends to overwhelm any absorption seen within a superbubble. We have observed four sight lines toward LMC superbubble N70 and see an excess of OVI absorption in comparison to four nearby, field sight lines. We interpret this excess OVI absorption, which amounts to log N_OVI14.05 or approx 60 percent greater than is seen in the comparison sight lines, as the signature of hot gas within N70, however, it is possible that this reflects normal variation in the halo of the LMC. A detection of OVI in emission from N70 would seal the case for a warm-hot component in superbubbles. Emission and absorption data together will constrain physical density and the mechanism through which OVI is produced in superbubbles. We propose to place two LWRS apertures on N70 and attempt to measure diffuse OVI and CIII emission from the superbubble. Prop ID: G054 Proposer: Gruendl Institution: University of Illinois Proposal Title: Hot Gas in the Starburst Carina Nebula The Carina Nebula is the nearest example of a starburst region. At a distance of approx 2 kpc, its stellar content and interstellar structure can be resolved and studied in detail. The mechanical energies injected by massive stars have yielded a large amount of hot, X-ray-emitting gas in the Carina Nebula. Optical and X-ray observations reveal a complex relationship between 10^4 K and 10^6 K gas components. We request FUSE observations of the Carina Nebula to use emission lines to study both the physical conditions and kinematic properties of the hot gas in X-ray-emitting regions. In particular, we will use the OVI emission lines, in conjunction with complementary X-ray and optical data, to study SNR shocks and interfaces between hot >10^6 K) gas and the surrounding cooler (10^4 K) shell gas. The results will aid in our understanding of the generation and conditions of hot gas in distant, unresolved starburst regions. Prop ID: G055 Proposer: McCandliss Institution: Johns Hopkins University Proposal Title: Far-Ultraviolet Observations of N11B -- Searching for Extragalactic Molecular Hydrogen Emission Recent studies of galactic reflection nebulae have revealed strong variations in the relative contributions from dust scattered starlight and fluorescent molecular hydrogen emission in their far-ultraviolet spectra. These differences are seen to be correlated with the environmental characteristics of the nebulae and have led to improved models of the ultraviolet fluorescence of molecular hydrogen. We propose to extend this study beyond the Milky Way with FUSE observations of the star-forming nebula N11B in the Large Magellenic Cloud. With several stars of spectral type B1 and earlier, we suggest that N11B is an external analog to the Orion Nebula (M42). The unique bandpass and spectral resolution of FUSE will enable an unprecedented study of extragalactic dust and may provide the first detection of far-ultraviolet molecular hydrogen emission outside the Milky Way. These observations will complement our ongoing study of galactic nebulae by probing new environmental variables such as grain composition and metallicity. Prop ID: G056 Proposer: Brown Institution: University of Colorado Proposal Title: Stellar Activity in the 30 Myr old Tucana-Horologium Association We propose a FUSE survey of stellar activity among the members of the Tucana-Horologium Association with dec < -50 deg, using the O VI and C III transition region emission lines as diagnostics of the transition region (10^5 K) activity. This set of stars is a 30 million year old subgrouping within the Local Association. These spectra will significantly expand the sample of young active, zero-age-main-sequence (ZAMS), F-M stars with measured transition region emission line fluxes, and allow direct comparision with the younger (12 Myr) beta Pic Moving Group stars, from our Cycle 6 FUSE Legacy program, and other older stars from the AB Dor (50 Myr) and Pleaides (100 Myr) Moving Groups. These spectra will allow detailed studies of the influence of stellar activity on the immediate circumstellar environment of young stars during the crucial phases of protoplanetary system formation, when the formation of gas giant planets and smaller terrestrial planets is underway. The sample chosen for this study have identical ages and formed together during the same star formation episode. By studying such samples of low and intermediate mass stars with identical ages and formation history, a clearer determination of the factors controlling stellar magnetic activity can be obtained, thus enabling better characterization of the evolution in stellar activity during the crucial early phases of stellar, circumstellar disk, and protoplanetary system evolution. Prop ID: G057 Proposer: Dunne Institution: University of Illinois at Urbana-Champaign Proposal Title: OVI Emission from the Interface Layers in the Superbubbles DEML152 and DEML192 We are studying the interface between the the hot (approx 10^6K) interior and the cooler (approx 10^4K) swept-up shell of superbubbles. Heating and cooling processes operating in these interface layers determine the structure and evolution of the associated astronomical objects. OVI lines are good tracers for the approx 10^5K gas of the interface layer. Thus, FUSE is an excellent instrument with which to study such interfaces. Previous studies of the interface layer have attempted to detect O^(+5) ions in absorption against probe stars within the superbubble s, but the OVI absorption from the interface is confused by hot halo gas and prevalent H_2 absorption lines. These problems are mitigated by observing OVI in emission. We therefore request new FUSE observations to search for OVI emission from the interface layers of two superbubbles in the LMC, DEM L 152 and DEM L 92. These FUV data will allow us to probe the 3E10^5K gas in the interface layer and, combined with previously obtained optical and X-ray data, to determine the physical parameters of the interface layer. Prop ID: G058 Proposer: Espey Institution: Trinity College Dublin Proposal Title: Understand Mass-loss in Cool Giants the Wind of SY Mus For the majority of red giant stars the basic mass-loss processes at work are unknown. Indeed, for stars of spectral types between K0 III and M5-M6 III, much remains unknown about the regions above the visible photosphere and the transportation of the processed material outwards to the ISM. Theories and models are in need of observational constraint, and in particular it is vital to derive spatially resolved information throughout the wind acceleration region within a few giant radii of the stars photosphere. Eclipsing symbiotic binary systems, consisting of an evolved giant in orbit with a white dwarf, provide an opportunity to take advantage of the finite size of the hot component to probe different levels of the chromosphere and wind acceleration region in absorption. This provides spatially resolved thermal, ionisation and dynamic information on the wind which can then be compared against predictions of hydrodynamical stellar atmosphere codes. We propose 6 observations of the symbiotic SY Mus utilizing the 0 day periodicity inherent in FUSE scheduling to phase space the observations. Results will be compared to PHOENIX hydrodynamical models and to similar observations of earlier spectral type symbiotic giants to constrain wind acceleration and chromospheric models. Prop ID: G059 Proposer: Blair Institution: Johns Hopkins University Proposal Title: The Enigmatic Magellanic Cloud Supernova Remnant N63A We propose follow-up FUSE observations of the supernova remnant N63A in the Large Magellanic Cloud. This remnant is within an OB association whose main sequence turn-off mass is 30 solar masses, and yet no evidence of the stellar ejecta is obvious. It was observed at one central position as part of the FUSE Magellanic Cloud SNR survey project. The LWRS aperture position was dominated by a bright optical shocked cloud, and a strong signal was seen in OVI lambda lambda 032,1038, but not in CIII lambda 977, the other strong line normally seen in strong radiative shocks. In this proposal, we request two short observations at offset positions to diagnose the eastern bright X-ray shock and the SW limb that shows two protrusions in the Chandra X-ray image of Warren et al. (2003) which are similar in appearance to ejecta-driven bow shock features seen in the Vela supernova remnant in our Galaxy. This small investment of time will provide a much clearer picture of FUV-emitting characteristics of this unusual supernova remnant. Prop ID: G060 Proposer: Guinan Institution: Villanova University Proposal Title: Towards Completing the FUSE dM Star Database - FUV Observations of the Old High Velocity dM1 Star SZ We propose to extend and expand our ongoing Sun in Time Program on solarstellar dynamo physics and X-rayFUV irradiance (and effects on planetary atmospheres) of solar-type (G0-5 V) stars to cooler, more numerous dM stars with deep convective zones (CZs). This proposal is also motivated by the upcoming exoplanetary search missions e.g. Kepler, SIM, and DarwinTPF) that will search for earth-like planets in the habitable zones of nearby G-K-M stars. Two years ago the program was extended to include FUSE Cycle 5 observations of a sample of dK0-5 stars of different ages. Here we propose a 40 ksec FUSE observation of a carefully selected representative old disk dM star -- SZ UMa -- which will help complete the parameter space of age, rotation, and FUV emission for dM stars. Also, we wish to explore the effect of the CZ depth on magnetic activity by comparing dwarf G, K, and M stars with similar rotation periods and ages. Of particular interest is the determination of X-rayFUV emission flux evolution with age for dM stars. This is because of the critical roles that FUV TR and chromospheric emissions (dominated by HI Lyman series and CIII and OVI emissions) play on the photochemical and photoionization evolution (and possible erosion) of planetary atmospheres and ionospheres. This program will also have a major impact on studies of FUV radiation and its effects on the environments of extrasolar planets that may be hosted by dM stars and on the possible origin and evolution of extraterrestrial life on such planets. We plan to combine the FUSE FUV observations with X-ray and UV (from IUE or HST, where available) to form spectral irradiance tables (flux at 1 AU) of dM stars covering a wide range of ages. With FUSE nearing the end of its usable lifetime, this may be the last chance to complete this important FUV dataset. Prop ID: G061 Proposer: Chayer Institution: Johns Hopkins University Proposal Title: FUSE Observations of Hot Subdwarf B Stars We propose FUSE observations of a sample of hot subdwarf B stars (sdB) in order to carry out an abundance analysis of heavy elements and see how their abundance patterns emerge from the observations. It is a well known fact that the atmospheres of these extreme horizontal branch stars exhibit abundance anomalies. Diffusion processes such as gravitational settling, radiative levitation, weak stellar winds, and accretion have been proposed to explain the abundance anomalies. Our goal is to identify which mechanisms operate in the atmospheres of these stars, study their interactions, understand the abundance patterns, and ultimately, constrain the structure of the atmospheres of sdB stars. With this proposal we want to complete our FUSE proposals E152 and F909 with targets that are feasible with the new FUSE. Only four sdB stars out of forty have been already observed within these two programs, and only three more targets are still feasible. This is why we propose observations of a new sample of sdB stars that can be done with the new FUSE. To study and interpret the abundance patterns in sdB stars, we need a large sample of stars with atmospheric parameters that cover the whole effective temperature and gravity domains (20,000 K < T_eff < 40,000 K ; 5.0 < log g < 6.5). To achieve a thorough abundance analysis we need FUSE observations, because many resonance lines of elements such as phosphorus, sulfur, chlorine, iron peak elements, and elements beyond the iron group are only visible in the FUV range for the effective temperatures of interest. This study will not only provide new insights into the stellar atmosphere structure of sdB stars, but also to the evolution of galaxies since these stars are the most important candidates for the source of the UV excess in elliptical galaxies and early-type spiral bulges. Prop ID: G062 Proposer: Wesemael Institution: Universite de Montreal Proposal Title: Trace Elements at the Photospheres of DB White Dwarfs The DB white dwarfs belong to the subgroup of white dwarf stars which possess an atmosphere dominated by helium. Their optical spectra are characterized by the transitions of neutral helium, and their effective temperatures range from 30,000 K to approximately 13,000 K. Trace elements are also occasionally seen in the atmosphere, principally hydrogen, but also a handful of heavy elements like carbon and silicon. To explain the abundance patterns of both dominant and trace elements, several processes must be called upon, namely upward diffusion of hydrogen left over from previous evolutionary phases, downward settling of heavy elements, convective dredge-up from deeper layers, convective mixing, accretion from the ISM, radiative element support, stellar winds etc. Our picture of the abundance patterns of trace elements remains sketchy, however, especially for the cooler DB stars. We propose to secure spectra for three DB stars spanning the effective temperature range between 14,400 and 17,900 K with the specific aims of obtaining abundances of several elements (principally C, but also Si, N, Fe) and of testing the reliability of our model atmospheres in that wavelength range. The FUSE observations will provide us with a unique opportunity to study the competing physical processes which affect the photospheric abundance of heavy elements in DB stars. Prop ID: G063 Proposer: Penny Institution: College of Charleston Proposal Title: The Effect of Metallicity of the Rotation Rates of Massive Stars Recent theoretical predictions for low metallicity massive stars predict that these stars should have drastically reduced equatorial winds (mass loss) while on the main sequence, and as such should retain most of their angular momentum. Observations of both the Be(B+Be) ratio and the blue-to-red supergiant ratio appear to have a metallicity dependence that may be caused by high rotational velocities. But to date only two studies of the rotation rates of massive stars have been completed. Their results differ, one finding that lower Z massive stars do rotate faster, one finding the opposite. In addition both studies have limitations. The first observed only stars with masses lower than 12 M_sun, which are not predicted by theory to have rotation rates affected by metallicity. The second had only a small sample, and one which may have been skewed to narrow-lined targets. The Multimission Archive at Space Telescope MAST) contains FUSE archival spectra of over 140 O-type stars in the Magellanic Clouds. This is a significantly large sample that can be used to address this question with directly measured projected rotational velocities in a low metallicity environment. The method to employ is that used in previous studies on both IUE and STISHST spectra (Penny 1996, Howarth et al. 1997, Penny et al. 2004). An UV spectrum of a test star is cross-correlated with a narrow-lined star to create a cross-correlation function (CCF). The width of this CCF is related to the intrinsic width of the spectral lines of the star. To determine projected rotational velocities, an accurate calibration must be found between CCF widths and V sin i values, for a sample of stars for which these values are already known. Archival FUSE spectra also exist for over 100 Galactic O-type stars with known projected rotational velocities. However there is a paucity of narrow-lined targets from the Galaxy available. This severely limits the calibration of CCF width to V sin i and results in overestimates of the latter from FUSE spectra. The acquisition of five additional narrow-lined stellar spectra will complete the calibration of CCF width to V sin i. And allow the huge archive of LMC and SMC O-type spectra to be used to its fullest potential. Prop ID: G064 Proposer: Charpinet Institution: Observatoire Midi-Pyrenees Proposal Title: Testing Mode Identification Techniques for sdB Pulsators with FUSE We propose to monitor the rapid pulsations of the hot subdwarf B (sdB) star Feige 48 in the Far UV using the Time Tag (TTAG) mode of FUSE. This star has recently been under detailed study using asteroseismic techniques based on standard optical white light photometry (Charpinet et al. 2005, A&A, in press). This analysis provided both very strong constraints on the fundamental structure of this star and a prediction of the nature of the pulsation modes being observed (i.e., the mode identification). This latter prediction can be checked independently using multi-waveband photometry. The apparent amplitude of a nonradial oscillation mode depends on both its geometry through the degree ell) and the wavelength at which it is observed. For hot sdB stars, calculations clearly indicate that the relative mode amplitudes as seen in the optical and in the Far UV strongly discriminates between values of the degree ell, allowing these to be easily determined. Such constaints on the mode identification are otherwise very difficult to obtain from optical multicolour photometry alone, as the discrimination between different ell values is weak when confined in this bandpass. The comparison of the FUV amplitudes of the modes detected by FUSE with their optical counterparts (from dedicated, simultaneous ground-based observations) will permit an independent determination of the degree ell of the pulsation modes of Feige 48. Our ultimate goal is to provide fundamental tests of the models that describe pulsating sdB stars and the techniques that are being developed to exploit their strong seismic potential. A consistency check of this kind offers a rare opportunity to validate asteroseismic tools that will be extensively used in the future to infer internal properties of subdwarf B stars. Prop ID: G065 Proposer: Dupuis Institution: Canadian Space Agency Proposal Title: Metals and Quasi-Molecular Satellites in Cooler DA White Dwarfs We are re-proposing a survey program of DA white dwarfs approved for cycle 6 with a list of targets more suited for the new pointing constraints caused by the loss of an additional reaction wheel on FUSE. This survey concentrates mainly on stars cooler than 20,000K but a couple of slightly hotter stars were included for increased flexibility of FUSE scheduling. Cooler DA white dwarfs have not been studied as extensively than hotter white dwarfs by FUSE as they tend to be fainter and are not good background sources for deuterium studies. We will search for the presence of trace elements such as C, N, Si, and Fe in the atmosphere of these cooler white dwarfs. Previous observations of white dwarfs in this temperature range have revealed surprisingly high metallicity in a subset of these stars. This is in spite of the dwindling of support by selective radiative acceleration at these temperatures. The current wisdom about this phenomenon is that these stars are accreting matter, either interstellar or circumstellar, which then pollutes their atmospheres. These observations will allow us to potentially discover new cool metal-enriched DAs and further our understanding of this peculiar phenomenon. These observations will also allow us to improve our understanding of quasi-molecular satellites which become prominent in the wings of Lyman beta and Lyman gamma profiles at these temperatures. Prop ID: G066 Proposer: Tripp Institution: University of Massachusetts - Amherst Proposal Title: Probing the Origin of O VI Emission from LMC X-3 We propose to monitor the UV and X-ray emission of the persistent black hole X-ray binary (XRB) star LMC X-3 in a coordinated FUSE and RXTE program. In FUSE Cycle 5, we detected OVI emission from LMC X-3, and we observed velocity shifts of the OVI emission at different orbital phases by up to 200 km s^(-1), in agreement with earlier FUSE observations reported by Hutchings et al. (2003). However, while Hutchings et al. observed very broad OVI emission that could arise in the black hole accretion disk, during our more recent observation the broad feature was greatly suppressed and we detected an additional much narrower OVI emission feature. The narrow OVI emission is strongest at orbit phase approx 0.5 (inferior conjunction) and disappears at phase approx 0 (superior conjunction). In principle, these OVI emission features could provide important constraints on fundamental parameters of the XRB such as the inclination of the system. However, a variety of interpretations remain viable, and the current FUSE observations are too sparse to support firm conclusions. To improve our understanding of the nature and implications of the OVI emission, we seek ten short observations during the course of FUSE Cycle 7, with nearly-simulataneous X-ray observations from RXTE. With these data, we will (1) obtain better measurements of the OVI velocity variations, (2) study the dependence of the OVI emission strength on orbital phase, (3) study how changes in the X-ray spectrum affect the OVI emission, and (4) investigate how the X-ray and UV emission (both OVI and continuum) are correlated. Prop ID: G067 Proposer: Ghavamian Institution: Johns Hopkins University Proposal Title: The Nebular Shell Around the Ultraluminous X-ray Source Ho IX X-1 -- Supershell or Hypernova Remnant We propose FUSE observations of a large shell associated with the ultraluminous X-ray source Holmberg IX X-1 (a.k.a. M81 X-9). The optical spectrum of the shell shows a classic shock spectrum, with strong SII relative to H alpha. The X-ray emission derives primarily from an embedded ultraluminous (approx 10^40 ergs s^-1) X-ray source (ULX). The source is pointlike and may be an accreting intermediate mass (100-1000 M_odot) black hole. Its relationship to the nebular shell is poorly understood. The shell may be a supershell blown by multiple stellar winds and SNe, or it may be the remnant of a single highly energetic (E > 10^53 ergs) explosion (i.e., hypernova). Understanding the kinematics of the shell will provide a critical clue to the origin of the X-ray source Ho IX X-1. We will search for CIII andor OVI and other FUV line emission from the shell and use the line ratios to constrain the shock speed. As a bonus, we also plan to search for emission from the compact photoionization nebula around the ULX itself. The measurement of OVI from this source would provide valuable information such as the absorbing column in the immediate vicinity of the compact object and the shape of the ionizing spectrum. The Ho IX X-1 shell is likely the only ULX with low enough extinction to be observable in the FUV, and is well-matched to the diffuse source capabilities of FUSE. Prop ID: G070 Proposer: Sankrit Institution: Johns Hopkins University Proposal Title: Survey of OVI Emission towards Nearby White Dwarfs We propose a survey of OVI emission along sight lines at small angular separation from nearby white dwarfs that have been observed by FUSE. The white dwarf spectra present a wide range of OVI absorption properties, ranging from no detectable OVI to circumstellar OVI. The results of our survey will allow us to characterize the relationship between emission and absorption along closely spaced sight-lines. In a companion (standard) proposal we have requested observations of the four best cases of emissionabsorption pairs of sight-lines. Those results will be used to obtain the physical properties of conductive interfaces in the local interstellar medium, which in turn will help us interpret the data obtained in this survey. Prop ID: G071 Proposer: Dixon Institution: The Johns Hopkins University Proposal Title: FUSE Observations of the High-Ionization Planetary Nebula around KPD 0005+5106 A high-ionization planetary nebula (PN) around the hot white dwarf KPD0005+5106 was discovered serendipitously by its photoionized OVI emission in FUSE observations. Because the data were taken as part of a calibration program, only two radii and a limited range of position angles are sampled by the discovery observations. We propose additional FUSE observations of the nebula in order to study the distribution of the OVI emission. Since the properties of the stars ionizing continuum and its distance are well constrained, the measurements will allow us to estimate the density of the emitting gas. High-ionization PNe should exist around most hot white dwarfs but are difficult to identify and study because they are faint and extended in the optical. Our proposed FUSE observations of one of the few known high-ionization PNe will yield important insights into the properties of this class of objects. Prop ID: G072 Proposer: Dixon Institution: The Johns Hopkins University Proposal Title: FUSE Observations of Hot Horizontal Branch Stars in the Globular Cluster NGC 6752 We propose FUSE observations of eight stars in the globular cluster NGC 6752. These stars span the full length of the clusters extended horizontal branch (EHB) and continue on into the post-EHB phase. By comparing its FUV spectrum with synthetic spectra derived from non-LTE stellar atmosphere models, we will derive the effective temperature, surface gravity, and photospheric abundances of each star. Our principal goal is to study the competing effects of gravitational settling and radiative levitation in the atmospheres of EHB stars by looking for variations in their abundances from the cluster mean and as a function of temperature. While ground-based observers have measured the abundances of cooler (< 20,000 K) blue horizontal branch BHB) stars in several clusters, the abundance ratios of EHB stars are unknown. Prop ID: G073 Proposer: Dixon Institution: The Johns Hopkins University Proposal Title: FUSE Observations of the UV-Bright Star in 47 Tucanae We propose FUSE observations of the hot post-asymptotic giant branch PAGB) star BS in the globular cluster 47Tuc. The star has been observed with the Hopkins Ultraviolet Telescope (HUT) and from the ground, and we seek to answer questions raised by those observations. Models fit to the stars FUV and optical spectra vastly over-predict the flux at wavelengths shorter than that of Lyman beta. What is the source of this excess opacity According to stellar evolution theory, stars that have undergone first dredge-up on the RGB should be enhanced in nitrogen and depleted in carbon. Its HUT spectrum suggests that the star is overabundant in nitrogen and underabundant in carbon, but the lines of both elements are are blended with interstellar features at the HUT resolution. By comparing the stars FUSE spectrum with synthetic spectra derived from stellar atmosphere models, we can determine the stars photospheric abundances and reconstruct the history of its chemical evolution and mass loss. Prop ID: G074 Proposer: Peters Institution: University of Southern California Proposal Title: Mass Transfer in the Active Interacting Binary UCephei Following the recent FUSE detection of a well-defined accretion hot spot in the Algol binary UCephei (P2fd493), an active system in which the gas stream strikes the mass gainers photosphere at a steep angle, we propose new observations to determine physical and geometrical parameters for the impact site and its apparently associated splash plasma. The capabilities of FUSE present us with an unparalleled opportunity to map a splash plasma in velocity and physical space, as many prominent shell-type absorption features are formed in this gas. Furthermore, the location, size, and temperature of the impact site can be well-determined because the flux contrast between the spot and the photosphere of the B7-8 mass gainer is large in the FUV. We propose a series of randomly spaced observations, each with a duration of 5 orbits (approx 10 ksec of observing time) and spanning a phase interval of 0.13 in the 60 hr period. Statistically half of the observations should fall in important phase interval .63-0.13 that includes totality and the transit of the hot spot through our line of sight. Based upon the results from previous FUSE observations of Algol binaries during total eclipse (Peters & Polidan 004) we expect that the stream impact produces a high-temperature circumstellar plasma abovebelow the orbital plane that emits in OVI. Totality observations of UCep would allow us to test a hypothesis that this bipolar flow is a result of an impact-produced splash of material. To increase the chance of observing the 2.3hr total eclipse that will enable us to map the location of the expected high-temperature plasma, we request 10 visits. The physical parameters that are obtained from the observations will constrain future 3-D hydrodynamical simulations of mass flow in Algols and enable an estimate of the amount of mass lost from the system during the Algol phase of evolution. Prop ID: G075 Proposer: Peters Institution: University of Southern California Proposal Title: A FUSE Survey of Be Stars in Galactic Clusters We propose a survey of Be stars that reside in galactic clusters to determine the abundances of carbon and nitrogen in their photospheres. During the past two decades there has been a consensus that the rotation rates in Be stars are rapid but far short of their critical values (0.50 < VV_cr < 0.85). But recently there has been a renewed interest in the possibility that Be stars are critical rotators Townsend, Owocki, & Howarth 2004). Abundance studies can provide a test for the latter hypothesis, as stellar evolution modeling by Meynet & Maeder (2000) has predicted a significant enhancement in the photospheric N abundances in very rapidly rotating OB stars due to mixing of CNO-processed material from their interiors. The FUV is the best spectral region for determining CN abundances in Be stars as the strongest lines of CII, III and NII, III fall in this region and the flux contribution from the disk is not important. The survey will include Be stars in h & ChiPer, a galactic cluster that contains a large fraction of Be stars, NGC 3766, and NGC 4755, and provide an independent test of the critical rotation hypothesis and contemporary stellar evolution models that include stellar rotation. Prop ID: G076 Proposer: Peters Institution: University of Southern California Proposal Title: The Abundances of Carbon and Nitrogen in the Be Star NGC330-B12 in the Small Magellanic Cloud We propose a FUSE observation of the Be star B12 in NGC330 in the Small Magellanic Cloud to determine the abundances of carbon and nitrogen in its photosphere. During the past two decades there has been a consensus that the rotation rates in Be stars are rapid but far short of their critical values (0.50 < VV_cr < 0.85). But recently there has been a renewed interest in the possibility that Be stars are critical rotators (Townsend, Owocki, & Howarth 2004). Abundance studies can provide a test for the latter hypothesis, as stellar evolution modeling by Meynet & Maeder (2000) has predicted a significant enhancement in the photospheric N abundances in very rapidly rotating OB stars due to mixing of CNO-processed material from their interiors. The FUV is the best spectral region for determining CN abundances in Be stars as the strongest lines of CII, III and NII, III fall in this region and the flux contribution from the disk is not important. The Be star B12 in NGC330 is ideal for an abundance analysis as it has relatively sharp lines. A recent abundance study from optical data (Lennon et al. 2005) suggested a low N abundance, but the result was inconclusive as it was based upon only one very weak line. The low N abundance in the SMC renders it an ideal environment in which to look for altered abundances due to rotational mixing. We also propose an observation of a well-known, sharp-lined non-emission B star in NGC 330 (B30) in order to be able to compare the CN abundances in NGC330-B12 with benchmark values for the cluster. Prop ID: G077 Proposer: Thilker Institution: The Johns Hopkins University Proposal Title: Probing Extranuclear Star-Forming Regions from SINGS NASAs Spitzer Space Telescope and Galaxy Evolution Explorer (GALEX) now provide high-resolution MIR--FIR and FUV--NUV probes for the internal structure of nearby galaxies, effectively constraining the spatial distribution of dust and stars of varied age. Both observatories have committed to a common Legacy project to ascertain the star formation activity and its effect on dust properties in a large representative sample of local targets. This effort is called SINGS -- the Spitzer Infrared Nearby Galaxies Survey. Highlighted within SINGS are a collection of 75 optically- or IR-bright star-forming regions, for which dedicated high-resolution IR (5-37 mu m) spectroscopy will be obtained. In order to best capitalize on this opportunity to gauge the entire (stellar and dust) FUV--FIR SED for such intermediate luminosity starbursts, we propose FUSE observations for 14 optically-selected, extranuclear star-forming regions in three SINGS galaxies. The proposed sample benefits from completed GALEX FUV and NUV imaging, which we have used to assess feasibility. The extranuclear SINGS star-forming regions span a representative range of key physical parameters. The FUSE spectra of these star-forming regions, when combined with GALEX and Spitzer observations, will constrain the massive stellar content in each object and permit determination of the UV attenuation law. We will also explore the possibility of using the equivalent width of NIV, CIII, and PV winds lines as metallicity indicators, with application at high redshift. Our FUSE dataset will have exceptional archival value, given the GALEXSINGS Legacy program. This proposal is a resubmission of our approved Cycle 6 Survey project (F918) from which no targets have yet been observed. Prop ID: G078 Proposer: Thilker Institution: The Johns Hopkins University Proposal Title: FUSE Survey Observations of UV-Bright Stellar Complexes GALEX has dramatically increased the number of galaxies in the local Universe for which sensitive, high-resolution UV imagery is available. In particular, our Nearby Galaxies Survey (NGS), Medium Imaging Survey MIS), and Deep Imaging Survey (DIS) have together provided FUV and NUV imaging observations at approx 5 arcsec resolution for 200+ galaxies with v <2500 kms and delta > 50 deg. In addition to establishing a benchmark for global UV galaxy morphology, these three core GALEX surveys have yielded an unprecedented sample of UV-bright stellar complexes which probe a diverse set of host environments. FUSE offers a superb opportunity to obtain FUV spectra for these stellar nurseries (intermediate-luminosity starbursts). As a class they harbor much of the star formation in normal galaxies, yet remain under-represented within the FUSE archive. We propose survey observations for a sample of 24 such UV-bright complexes in 12 nearby galaxies. FUSE spectra will constrain the massive stellar content in each object. We will further determine the equivalent width of NIV, CIII, and PV winds lines as a function of metallicity, setting up for their use as a high redshift metallicity indicator. The combination of FUSE, GALEX, and infrared (Spitzer, eventually JWST) observations of our sample will prove particularly powerful, delineating variations of the UV attenuation law versus environment. We have already initiated such panchromatic work. In a parallel effort approved for FUSE Cycle 6 F918) and in a follow-up Cycle 7 proposal, we are investigating a small number of extranuclear star-forming regions highlighted by SINGS the Spitzer Infrared Nearby Galaxies Survey) for which we have IRACMIPS imaging and 5-37 mu m spectroscopy to complement the UV observations. Similar Spitzer imagery is available for 10 of 12 galaxies we focus on here. IR spectroscopy will be proposed, but FUSE and GALEX now present a chance which should not be missed. Prop ID: G079 Proposer: Kaiser Institution: Johns Hopkins University Proposal Title: Probing the Origin of High-ionization Emission Lines in AGN with BLRG, 3C390.3 Radio galaxies with broad, double-peaked Balmer lines (BLRGs) occupy an important niche in our understanding of active galaxies because their profiles suggest that the emission occurs in the accretion disk. Observations in the UV, however, reveal that the high-ionization lines are not always double-peaked, implying perhaps that they are emitted in a weak wind. The OVI line, observable by FUSE in low redshift BLRGs, offers an important probe of the high-ionization line emission. The profile yields information about the kinematics of the line emitting region; the ratio of the OVI line with other high-ionization lines yields information about the ionization state and abundances in the emitting gas. Yet, despite the great promise that FUSE observations of BLRGs harbor, only one has been observed so far. We propose observations of the prototype double-peaked BLRG 3C390.3. It is one of the brightest double-peaked BLRGs and it has archival UV and optical spectra. In addition, it harbors a massive black hole (M_BH .9E8M_sun) and exhibits a low accretion rate (MM_Edd0.02). Thus, C390.3 presents a test of the extreme end of Eigenvector 1, which is believed to be related to the fraction of the Eddington luminosity at which the object is emitted. Prop ID: G080 Proposer: Gabel Institution: University of Colorado Proposal Title: Monitoring the Intrinsic Absorption in Mrk 817 Probing Feedback from AGN Outflows Recent theoretical models suggest AGN outflows may have a far-reaching global impact, playing a central role in the evolution of supermassive black holes, their host galaxies, the surrounding IGM, and cluster cooling flows. The mass outflow seen as UV and X-ray blueshifted absorption in AGN spectra may be the observational signature of these feedback mechanisms. To test this, detailed studies at high spectral resolution are needed to determine the physical conditions and geometry of the outflow. The Seyfert galaxy Mrk 817 is an ideal target for this. It has a far higher outflow velocity (v approx 4000 kms) than any other nearby AGN, thus providing a direct study of the energetic outflows likely to impact their environment. It also provides a unique study of the link between the ubiquitous Seyfert intrinsic absorbers and the more extreme systems seen in distant QSOs. Furthermore, it is one of the brightest AGNs at UV wavelengths, thereby allowing precise measurements of the absorption parameters. Previous observations have shown the intrinsic absorption in Mrk 817 is variable. We propose two new FUSE observations of Mrk 817. These will provide the constraints needed to isolate the variability mechanism (changes in ionic column density versus covering factor). Column densities, or limits, measured from the crucial O VI, H I, and C III lines in the FUSE bandpass will determine the total column density (N_H) and ionization of the outflow via photoionization modeling. Variability in the ionization structure will give limits on the distance of the absorber from the central engine. Variability in the covering factors or N_H will constrain the transverse velocities and geometry of the outflow. These results will allow us to measure the total kinetic luminosity of the outflow, which is needed to assess AGN feedback models. It will also provide important constraints on dynamical models of AGN outflows. Prop ID: G081 Proposer: DeWarf Institution: Villanova University Proposal Title: FUSE Observations of the Unprecedentedly Deep Quiescent Magnetic Activity State of alpha Centauri A A long standing problem and a central topic of solar-stellar connection studies is that of relating the Suns magnetic behavior to other stars. Our Sun is used as a fundamental calibration and as a reference point for stellar theory. This requires that the Suns expressions of activity (distribution of magnetic active regions, coronal densities, emergence of magnetic flux, etc.) are fundamentally normal for a star of its age and evolutionary history. Direct comparison with true solar analogs is critical for both understanding the magnetic nature of the Sun as well as magnetic phenomena in other stars. alpha Cen is the nearest stellar system to our Sun. The G2V primary (alpha Cen A) is an almost perfect solar analog with regard to its mass, radius, temperature, and convection zone depth, but is slightly older (tau approx 5-6 Gyr) than our Sun. These properties are well determined through extensive studies, making it an ideal Sun-as-a-star comparison to test solar concepts. Recently, X-ray emission fluxes for alpha Cen A were observed to diminish by a factor of nearly 25(), a phenomenon never before observed for the Sun of any solar-aged star. The XMM observations imply that the chromospheric through coronal regions of alpha Cen A can be highly variable, with changes in both mean temperatures and, to a larger extent, the emission measures necessary to address these new observations. The requested FUSE observations are crucial to a program to examine the long-term magnetic activity cycle of alpha Cen A. We hope to observe alpha Cen A during Cycle 7 to obtain high quality FUV spectra during this unprecedented, very deep quiescent state of this up til now normal solar-type star. These FUSE observations will be compared to the FUSE spectra secured in 2001 to search for differences in line strengthsprofiles along with carrying out detailed emission measure analysis. We will coordinate these FUSE observations with the XMM observations of the target that are planned by a European group. Prop ID: G082 Proposer: Malkan Institution: University of California Proposal Title: Simultaneous Multiwavelength Spectra of High-Z Quasars--Physical Nature of the EUV Continuum We propose FUSE spectroscopy of three newly discovered high-redshift Sloan quasars (1.5 < z < 2.2) and the only known EUV variable quasar HS 1700+6416 (at z 2.73). These redshifts give us the ability to measure the EUV continuum below 400AA -- where only four quasars have ever been observed. Combining these FUSE spectra with simultaneous observations by GALEX, XMM, and from the ground, we will obtain the first complete measurements of the quasar continuum SED across its energy peak, and over the range where most of its photoionizing power is emitted. These determinations of the full ionizing spectrum of quasars have strong implications for the evolution of the IGM and the evolution of structure in the Universe, as well as for quasar emission lines and efforts to weigh their black holes through reverberation mapping. By obtaining complete SEDs of 1700+6416 at two epochs, we will determine whether its surprisingly strong EUV variability is correlated with changes at higher andor lower energies. These data will provide the strongest tests yet of competing physical models of the central engine, such as a black hole accretion disks with Comptonizing corona. If we manage to detect the rest frame continuum down below 304AA, we will measure HeII Ly alpha absorptions. These quasars are the brightest known in the u-band, and have extremely low levels of Milky Way extinction. Only a handful of quasars have ever been detected in the EUV shortward of 600AA, and FUSE is the only operating spectrograph which can obtain any further such data. Prop ID: G083 Proposer: Herczeg Institution: Caltech Proposal Title: The Molecular Hydrogen Column Density In Our Line of Sight To CTTSs Estimating the extinction to CTTSs has historically been difficult because the accretion continuum complicates measurements of the photospheric emission. We propose to use FUSE spectra of three CTTSs to measure the H_2 column density in our line of sight. We will then use this measurement to infer a total hydrogen column density, thereby constraining the extinction in our line of sight to these CTTSs. A low N(H_2) will strongly indicate that the extinction is negligible, while a high N(H_2) will yield a reasonable estimate for A_V that will ultimately need to be complemented with future N(HI) measurements with the next generation of UV spectrographs for an accurate extinction estimate. Previous studies of four CTTSs have demonstrated that the extinction estimates can differ by A_V>1.0 mag between this technique and previous, less reliable techniques. Prop ID: G084 Proposer: Holberg Institution: University of Arizona Proposal Title: FUSE Observations of the Pre-Intermediate Polar HS1136+6646 HS1136+6646 is a close binary system consisting of a hot DAO primary and a secondary of spectral type K7. It is classified as a post-common envelope pre-cataclysmic variable binary. Recent FUSE and HST observations have shown this system to be one of only three known pre-intermediate polar systems known as well as the most massive pre-cataclysmic variable. This system has been well observed from the ground, and the system parameters are now well known. Spaced based FUV and UV spectra have revealed intriguing details of the magnetic nature of the hot white dwarf including correlations between the white dwarf spin phase and shape of the O VI line profiles. We propose follow-up FUSE observations that focus on the discoveries regarding the magnetic nature of HS1136+6646. The proposed observations, along with existing FUSE data, will increase our sensitivity, making possible our two main objectives. One, a mapping of the O VI line shape variations with respect to the spin phase of the white dwarf as well as planned ground based spectropolarimetric observations. Second, an intensified search for spectroscopic evidence of photospheric abundance inhomogeneities and changing line shapes using phase resolved spectra. (81 rows affected)