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Daily 3662
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3662 PERIOD COVERED: DOYs 208-209 OBSERVATIONS SCHEDULED ACS/HRC 9974 Mid-Ultraviolet Spectral Templates for Old Stellar Systems We propose a three-year program to provide both observational and theoretical mid-ultraviolet {2300A -- 3100A} spectral templates for interpreting the age and metallicity of globular clusters and elliptical galaxies from spectra of their integrated light. The mid-UV is the region most directly influenced by stellar age, and is observed directly in optical and infrared studies of high-redshift quiescent systems. The reliability of age and metallicity determinations remains questionable until non-solar metallicities and abundance ratios are considered, and stars spanning the color-magnitude diagram are included, as we propose here. With archival HST STIS spectra we have improved the list of mid-UV atomic line parameters, then calculated spectra from first principles which match observed spectra of standard stars up to one- fourth solar metallicity. We will extend both observations and calculations to stars of solar metallicity and beyond, and to those in short-lived stages hotter than the main-sequence turnoff, stars not currently well-represented in empirical libraries. The necessary line-list improvements will come from new high-resolution mid-UV spectra of nine field stars. A key application of the results of this program will be to the old systems now being discovered as `Extremely Red Objects' at high redshifts. Reliable age-dating of these places constraints on the epoch when large structures first formed in the universe. STIS/CCD/MA1/MA2 9871 AALs in Quasars: Diagnostics of the Environment Associated absorption lines {AALs} in quasar spectra carry a wealth of information on the gas-phase kinematics, ionization states, column densities, outflow masses, and elemental abundances near the quasars. Most of the existing UV spectra have low spectral resolution, which hampers efforts to accurately determine these properties at low redshifts. We propose medium-resolution FUV and NUV STIS spectroscopy, more than an order of magnitude improvement in spectral resolution over previous studies, to observe a sample of AAL quasars at redshifts and luminosities intermediate between the nearby Seyferts and the bright, high-z quasars. Our aim is to determine basic physical parameters for the absorbers, measure the abundances, search for AAL variability, and constrain the location of the absorbers relative to the central quasars. A unique aspect of our z~0.2 sample is the ability to get both UV and X-ray diagnostics, thus allowing us to perform a joint analysis of our STIS data with X-ray observations to further constrain the full range of ionizations and column densities of the UV/X-ray absorbing gas. NIC3 9846 The Origins of Sub-stellar Masses: Searching for the End of the IMF Is there a preferred scale that defines the end of the IMF? We propose to test this hypothesis by conducting a deep spectroscopic survey of extremely low mass objects in the embedded young cluster associated with NGC1333. At a distance of only 300pc, this cluster is one of the nearest examples of a dense young cluster. We will be able to obtain R=200 spectra and photometry for 40-60 cluster members with masses between 5-40 Jupiter masses at an age of 1 Myr observed through A{v}10 mag. This will enable us to estimate temperatures and luminosities for all sources detected in the survey. We will compare their positions in an H-R diagram to PMS evolutionary tracks in order to estimate their ages and masses. For a solar metallicity cloud at a temperature of 10 K, the minimum mass for fragmentation is thought to be 10 Jupiter masses. A statistically significant sample of objects detected below this limit would challenge the role of hierarchical fragmentation in limiting substellar masses. The proximity of this cluster combined with the unique sensitivity, wavelength coverage, and multi-object spectroscopic capability of NICMOS on HST make this experiment possible. ACS/WFC 9842 A Snapshot Search for Halo Very-Low-Mass Binaries We propose a snapshot search for binary M subdwarf stars. These nearby stars have high velocities and low metallicies that identify them as members of the old Galactic halo {Population II}. ACS imaging is requested to search for secondary companions. This supplements a previous snapshot program that only obtained 10 observations. The observed binary fraction will be compared to the disk M dwarf fraction to look for differences in star formation. It is likely that a system suitable for orbital mass determinations will be found. In this case, future HST observations could determine the first masses for very-low-mass, low-metallicity stars. STIS 9786 The Next Generation Spectral Library We propose to continue the Cycle 10 snapshot program to produce a Next Generation Spectral Library of 600 stars for use in modeling the integrated light of galaxies and clusters. This program is using the low dispersion UV and optical gratings of STIS. The library will be roughly equally divided among four metallicities, very low {[Fe/H] lt -1.5}, low {[Fe/H] -1.5 to -0.5}, near-solar {[Fe/H] -0.3 to 0.1}, and super-solar {[Fe/H] gt 0.2}, well-sampling the entire HR-diagram in each bin. Such a library will surpass all extant compilations and have lasting archival value, well into the Next Generation Space Telescope era. Because of the universal utility and community-broad nature of this venture, we waive the entire proprietary period. STIS/CCD/MA1 9778 Probing Outflowing Winds from the Galactic Center We propose to use two extragalactic sightlines to probe our own Galaxy's "starburst" wind emanating from the Galactic Center. While new infrared imaging and spectroscopy have detected massive stars and very recent {3x10^6 yrs} star formation in the Galactic Center region, only indirect evidence {e.g., radio loops and arcs, bi-conical cavity edges seen in the mid-IR} exists for a wind. However, these winds are routinely detected from starbursts in other galaxies. Far-UV STIS echelle spectroscopy {E140M} of two targets on either side of the Galactic Center at {l, b}={350,-33} and {349, 55} will allow us to map the kinematics of outflowing gas in high ionization species of N V, Si IV and C IV. Similar spectra of distant {1.5-5 kpc}, bright B stars in the same regions of the sky will allow us to remove foreground contaminating components due to the Sco-Cen OB associations. Lower resolution STIS first-order and FUSE spectra show highly redshifted gas in N V and O VI respectively along these sightlines; these new observations will provide three times better spectral resolution {7-10 km/s in the 1185-1580A region} so that the kinematic signature of the outflow can definitely be detected. The foreground stars will allow us to determine whether the outflow is from the Galactic Center or the Sco-Cen OB associations. Absorption line column densities will be used to estimate the outflowing mass and energy by assuming a metallicity and ionizing source for the gas. WFPC2/ACS/WFC 9761 A morphological study of EROs and sub-mm sources in a unique deep field We propose a deep I-band ACS WFC survey in a unique deep field, focusing on two classes of high-redshift galaxy which are believed to be the progenitors of today's massive ellipticals: {1} our recently-studied deep sample of 158 "extremely red objects" {EROs}; {2} a complete flux-limited sample of 14 SCUBA sub-mm sources, which may represent the formation episode of the most massive galaxies at high redshift. The basic goals are to go deep enough to obtain morphological parameters for this large sample {e.g. scale-lengths and shape parameters} to investigate whether, for example, the EROs have sizes comparable to present day elliptical galaxies. Likewise, what are the typical size scales and morphologies for the SCUBA sources? Can we visualize their formation from smaller fragments? We can achieve both goals in a single contiguous field with a mosaic of 8 deep ACS WFC fields, requiring 16 orbits. STIS/CCD/MA1 9736 Integrated Absorption- and Emission-Line Analysis of Nebulae Serious discrepancies have arisen in CNONe abundance determinations for galactic nebulae in the past ten years depending upon which type of emission lines are used in the analysis: forbidden vs. permitted lines. The cause of the discrepancies, which can exceed an order of magnitude for some PNe, has been studied intensively but is still unknown. Emission line abundances cannot be considered reliable until the nature of these contradictory results is understood. We have developed a technique for integrating absorption lines into emission analyses for diffuse nebulae that provides an independent check on the validity of emission-line analyses. It requires high resolution observations of UV resonance absorption produced by the nebular gas in imbedded or background stars together with optical spectra of the nebulae. We propose to obtain UV spectra of four PNe central stars with STIS that will provide data necessary to exploit the new technique of integrated abundance determination that combines both emission and absorption lines. NIC1/NIC2/NIC3 8793 NICMOS Post-SAA calibration - CR Persistence Part 4 A new procedure proposed to alleviate the CR-persistence problem of NICMOS. Dark frames will be obtained immediately upon exiting the SAA contour 23, and every time a NICMOS exposure is scheduled within 50 minutes of coming out of the SAA. The darks will be obtained in parallel in all three NICMOS Cameras. The POST-SAA darks will be non-standard reference files available to users with a USEAFTER date/time mark. The keyword 'USEAFTER=date/time' will also be added to the header of each POST-SAA DARK frame. The keyword must be populated with the time, in addition to the date, because HST crosses the SAA ~8 times per day so each POST-SAA DARK will need to have the appropriate time specified, for users to identify the ones they need. Both the raw and processed images will be archived as POST-SAA DARKSs. Generally we expect that all NICMOS science/calibration observations started within 50 minutes of leaving an SAA will need such maps to remove the CR persistence from the science images. Each observation will need its own CRMAP, as different SAA passages leave different imprints on the NICMOS detectors. NIC2 10228 Multi-color HST imaging of the GJ 803 debris disk We propose to conduct a comprehensive high angular resolution study of the newly discovered debris disk around GJ 803. This nearby, young star has an estimated age of 8-20 Myr, a critical epoch in disk evolution and planet formation. By virtue of its proximity {10 pc} and nearly edge-on orientation, GJ 803's disk has an exceptional surface brightness and angular size relative to other disks resolved in scattered light thus far. Hence, this system offers an exciting new opportunity to study debris disks. Our proposed ACS and NICMOS imaging will elucidate the disk morphology, ascertain the grain properties as a function of radius, and search for fine dynamical structure indicative of the presence of planets. ACS WFC and NICMOS coronagraphic imaging will explore the inner disk, which includes the ~17 AU inner disk hole inferred from the star's spectral energy distribution. Complementary ACS WFC imaging will probe the outer disk {70 AU}; at such large distances around GJ 803, dust evolutionary timescales are longer than the stellar age, and hence we can study the composition of primordial circumstellar material. The combined dataset will provide the most comprehensive study to date of a debris disk from ~7 AU to ~200 AU radius. STIS/CCD 10222 The Next Generation Spectral Library We propose to complete our snapshot program to produce a Next Generation Spectral Library of 600 stars for use in modeling the integrated light of galaxies and clusters. This program is using the low dispersion UV and optical gratings of STIS. The library will be roughly equally divided among four metallicities, very low {[Fe/H] -1.5}, low {-1.5 [Fe/H] -0.5}, near-solar {-0.3 [Fe/H] 0.1}, and super-solar {[Fe/H] 0.2}, well-sampling the entire HR-diagram in each bin. Such a library will surpass all extant compilations and have lasting archival value, well into the Next Generation Space Telescope era. Because of the universal utility and community-broad nature of this venture, we waive the entire proprietary period. ACS/WFC 10120 The Formation Histories and Dynamical Roles of X-ray Binaries in Globular Clusters Close binaries are fundamental to the dynamical stability and evolution of globular clusters, but large populations have been extremely difficult to identify. Chandra X-ray images provide a revolutionary resource, revealing a few to dozens of low-luminosity X-ray sources in every cluster deeply examined; our own Chandra programs uniformly study these ubiquitous X-ray sources {close binaries and their progeny} in 11 clusters. However, definitive understanding of the nature of the various X-ray subpopulations requires the identification of optical counterparts, and HST is the demonstrated key in these crowded environments. We thus propose a proven, efficient, and uniform, HST multicolor imaging program for optical identifications in 6 of our clusters with Chandra data on-hand, but which lack adequate optical images in the HST archive. The proposed ACS images will permit statistical classifications into the various subtypes: CVs, qLMXBs, BY Dra's/RS CVn's {and MSPs}. A unique aspect of our program is that our clusters span a range of physical properties such as central concentration, cluster size, and mass--essential ingredients in the formation, evolution, and dynamical roles of cluster binaries. Exploiting this range of properties, we have identified a relation that provides the first compelling link between the number of X-ray sources and the predicted stellar encounter frequency in globular cluster cores. But further progress in understanding the details implicit in this relationship {e.g., whether CVs and qLMXBs formed primarily via stellar encounters, while BY Dra's/RS CVn's are mainly primordial binaries} demands uniform optical identifications for multiple clusters, spanning the full range physical properties. FGS 10103 FGS Astrometry of a Star Hosting an Extrasolar Planet: The Mass of Upsilon Andromedae d We propose observations with HST/FGS to determine the astrometric elements {perturbation orbit semimajor axis and inclination} produced by the outermost extra-solar planet orbiting the F8V star Upsilon Andromedae. These observations will permit us to determine the actual mass of the planet by providing the presently unknown sin i factor intrinsic to the radial velocity method which discovered this object. An inclination, i = 30degrees, within the range of one very low precision determination using reanalyzed HIPPARCOS intermediate data products, would produce the observed radial velocity amplitude, K = 66 ms with a companion mass of ~8 M_Jupiter. Such a mass would induce in Upsilon Andromedae a perturbation semi-major axis, Alpha = 0arcs0012, easily within the reach of HST/FGS fringe tracking astrometry. The proposed observations will yield a planetary mass, rather than, as previous investigations have done, only suggest a planetary mass companion. WFPC2 10072 WFPC2 CYCLE 12 INTERNAL MONITOR This calibration proposal is the Cycle 12 routine internal monitor for WFPC2, to be run weekly to monitor the health of the cameras. A variety of internal exposures are obtained in order to provide a monitor of the integrity of the CCD camera electronics in both bays {gain 7 and gain 15}, a test for quantum efficiency in the CCDs, and a monitor for possible buildup of contaminants on the CCD windows. WFPC2 10071 WFPC2 CYCLE 12 Supplemental Darks Part 3/3 This dark calibration program obtains 3 dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. WFPC2 10068 WFPC2 CYCLE 12 Standard Darks This dark calibration program obtains dark frames every week in order to provide data for the ongoing calibration of the CCD dark current rate, and to monitor and characterize the evolution of hot pixels. Over an extended period these data will also provide a monitor of radiation damage to the CCDs. ACS/HRC/WFC 10061 CCD Daily Monitor This program consists of basic tests to monitor, the read noise, the development of hot pixels and test for any source of noise in ACS CCD detectors. This programme will be executed once a day for the entire lifetime of ACS. STIS/MA1 10034 Cycle 12 MAMA Dark Monitor This test performs the routine monitoring of the MAMA detector dark noise. This proposal will provide the primary means of checking on health of the MAMA detectors systems through frequent monitoring of the background count rate. The purpose is to look for evidence of change in dark indicative of detector problem developing. STIS/CCD 10020 CCD Bias Monitor - Part 2 Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up high-S/N superbiases and track the evolution of hot columns. STIS/CCD 10018 CCD Dark Monitor-Part 2 Monitor the darks for the STIS CCD. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) None COMPLETED OPS REQs: 17230-2 Off-line +B SPA Trim Relay @ 209/16:10z 17231-0 Increase Battery 5 VTFE @ 209/16:18z OPS NOTES EXECUTED: 1246-0 Battery 5 Capacity Test Ground Limits @ 208/19:10z 1253-0 Battery 5 Pres Limit Changes Post Batt Capacity @ 208/19:15z SCHEDULED SUCCESSFUL FAILURE TIMES FGS GSacq 22 22 FGS REacq 10 10 FHST Update 30 30 LOSS of LOCK SIGNIFICANT EVENTS: Successfully off-lined +B SPA Trim Relay at first opportunity 209/16:10Z (OR 17230-2 with attached script). A complement of SA 3 strings is being kept off-line to optimize the battery full charge rate. The +DD SPA (4-string, Battery 1) has been kept off-line since Day 147 for this purpose. Since Battery 1 will undergo a capacity test in the next few weeks, need to reconfigure the charge-optimization configuration to avoid complexity in the Battery 1 Capacity Test script and promote recovery of Battery 1 following the discharge. Brought the +DD SPA (4-string, Batter 1) back on-line and took the +B SPA (4-string, Battery 4) off-line. Successfully increased Battery 5 VTFE Curve @ 209/16:18Z (OR 17231 with attached script). Following the uplinks, EPS SE monitored the power system operations from the console in the MOR for two orbits to verify nominal operation of TRSWCC (+B SPA Trim Relay disconnected, commanded relay order upon Trickle Charge initiation, Battery 5 VTFE cut-off, etc.). The batteries experienced Trickle Charge durations during the first and second orbits of 37 minutes and 42 minutes, respectively. EPS SEs continued to closely monitor the power system performance, especially battery temperatures and pressures, to assess the effect of these changes. |
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