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Daily 3754
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3754 PERIOD COVERED: DOYs 345-347 OBSERVATIONS SCHEDULED ACS/WFC/HRC 9895 The Role of Groups in the Evolution of Galaxies at Intermediate Redshifts Groups are the most common environment experienced by galaxies, yet they remain the least studied. The tidal fields and dynamical friction encountered by galaxies in groups probably holds the key to understanding the role of environment in driving the evolution of galaxies since z ~ 1. To study the evolution of galaxies in the group environment, we propose the first unbiased HST study of groups at moderate redshifts. Unlike previous HST group samples, that relied on radio or X-ray properties, our kinematically selected sample is drawn from a large redshift survey and is not biased towards unusually dense groups. HST imaging is essential to determine the morphology of galaxies in these systems and contrast this with the properties of galaxies in denser and more evolved groups and rich clusters at these epochs. HST data are also required to adequately compare the properties of groups at intermediate redshifts with local group samples derived from the 2df and Sloan surveys. We will combine the HST images with deep ground-based observations to study how morphologies and stellar populations of galaxies in groups have evolved in time. These observations are key to understanding the decline in the volume averaged star formation rate in the universe. S/C/NIC3 9832 A Search for Water Vapor in the Atmosphere of an Extrasolar Planet We propose to search for evidence of water vapor in the transmission spectrum of the transiting planet of HD 209458. A successful detection would not only establish the presence of this important atmospheric constituent, but would also constrain other key properties of this close-in, Jupiter-sized planet. Specifically, relating the absorption caused by water to that already observed from atomic sodium would help establish the height of the atmosphere's uppermost cloud layer {if any}. Also, the abundance of water will provide information about that of oxygen, and by extension, that of all heavy elements. To make this measurement, we propose a doubly-differential procedure in which we will use NICMOS in spectroscopic mode to detect the small spectral changes that occur during planetary transits, and that result from absorption of starlight as it passes through the outer parts of the planet's atmosphere. We search for water because it is expected to produce by far the strongest spectrum features within the wavelength range accessible to HST. ACS/WFC/WFPC2 9392 The Ancient Stars of M32 The question of whether the dwarf elliptical galaxy M32 contains a population of truly ancient stars has remained unsettled for decades. We recently used HST/WFPC2 to identify for the first time a population of RR Lyr stars in this galaxy. Since these stars are known only to be present in stellar populations older than 8-10 Gyr, we contend that M32 does possess an old stellar component and certainly cannot be comprised of only intermediate-age {~ 5 Gyr} stars as has been frequently suggested in the literature. Our earlier observations were insufficient to determine even the most basic photometric properties of these stars. Nor could we use the data to identify independent evidence of the old population that could help constrain just what fraction of the galaxy's stars are ancient. We propose new HST/ACS observations to {a} get periods and luminosities of the previously observed RR Lyr stars, {b} search for additional RR Lyr stars in a significantly larger volume of M32, and {c} obtain ultra-deep 2-color photometry to study the ancient main-sequence turnoff region of that galaxy directly, {d} look for radial population gradients in M32, both among the RR Lyr/Horizontal Branch and main- sequence populations, {e} compare the M31/M32 old populations in terms of metallicity spread, and {f} use the RR Lyr stars to precisely determine the relative and possibly the absolute distances of M32 and M31's halo. FGS 9335 Masses of Pre-Main Sequence Binaries We propose to continue to map the orbits of young star binaries in the Taurus and Ophiuchus star forming regions. Our goal is to measure their masses dynamically. This is important because there are still no low mass young stars with reliably known masses so calculations of their evolution to the main sequence are uncalibrated. NIC1/NIC2/NIC3 8794 NICMOS Post-SAA calibration - CR Persistence Part 5 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. ACS/HRC 10401 A Proper Motion Search for Intermediate Mass Black Holes in Globular Clusters Establishing the presence or absence of intermediate-mass black holes {IMBH} in globular clusters is crucial for understanding the evolution of dense stellar systems. We propose a systematic search for IMBHs by conducting an imaging/proper motion study of the centers of five of the closest, most centrally concentrated Galactic globular clusters. ACS/HRC observations allow for accurate proper motion measurements for stars all the way into the center of each cluster. Our approach consists of exploiting the blue/near-ultraviolet wavelength range in each of cycles 13 and 14, in order to dim both the bright red giants and the background of faint red stars, hence alleviating the crowding problems experienced by previous studies. Both filter and target selection are critical for the success of this project, and no previous HST program has an appropriate combination to allow proper motion measurements for most stars into the very centers of crowded clusters. The velocity measurements will allow us to: {i} place constraints on the mass of a central black hole in each cluster {detailed calculations show that the proposed observations are sufficient to detect any central black hole with a mass as low as 3000 solar masses at the greater than 3 sigma level}; {ii} derive the internal velocity dispersion as a function of cluster radius; {iii} verify or reject previous reports of cluster rotation; and {iv} directly measure any velocity anisotropy as a function of radius. ACS/HRC/WFC 10367 ACS CCDs daily monitor- cycle 13 - part 1 This program consists of a set of basic tests to monitor, the read noise, the development of hot pixels and test for any source of noise in ACS CCD detectors. The files, biases and dark will be used to create reference files for science calibration. This programme will be for the entire lifetime of ACS. 10364 WFPC2 Cycle 13 CTE Monitor Monitor CTE changes during Cycle 13. WFPC2 10356 WFPC2 Cycle 13 Decontaminations and Associated Observations This proposal is for the monthly WFPC2 decons. Also included are instrument monitors tied to decons: photometric stability check, focus monitor, pre- and post-decon internals {bias, intflats, kspots, & darks}, UV throughput check, VISFLAT sweep, and internal UV flat check. NIC3 10337 The COSMOS 2-Degree ACS Survey NICMOS Parallels The COSMOS 2-Degree ACS Survey NICMOS Parallels. This program is a companion to program 10092. ACS/WFC 10326 The Morphological, Photometric, and Spectroscopic Properties of Intermediate Redshift Cluster Galaxies We will use the ACS/WFC to image 8 fields in the outskirts of the kT=5.8keV, X-ray cluster RX J0152-13 at z=0.83, for which we obtained imaging in four central fields during Cycle 11. The resulting wide-field mosaic of RX J0152-13 will enable direct study of the population of galaxies falling into this cluster and will provide a much needed comparison to our on-going wide-field study of the more massive, 10.5keV cluster MS1054-03 at the same redshift. Imaging RX J0152-13 to twice its viral radius enables us to: {1} trace the transformation of infalling field spirals into cluster early-types using, e.g., the morphology-density relation to large radii and very low local densities; {2} determine the importance of galaxy-galaxy interactions, i.e., whether the frequency of such encounters in the infall region is as unexpectedly high as found in MS1054-03; and {3} study in detail the star-formation histories of the most recently accreted members via accurate colors and morphologies. A comparison of RX J0152-13 with MS1054-03 will also allow us to directly probe the dependence of galaxy evolution on cluster mass. Only by pairing the wide-field ACS mosaic of RX J0152-13 with multi-object spectroscopy from the Magellan, Keck, and VLT telescopes can we test predictions from galaxy formation models, understand how field spirals evolve into early-type cluster members, and better constrain the formation of galaxies in general. ACS/HRC 10272 A Snapshot Survey of the Sites of Recent, Nearby Supernovae During the past few years, robotic {or nearly robotic} searches for supernovae {SNe}, most notably our Lick Observatory Supernova Search {LOSS}, have found hundreds of SNe, many of them in quite nearby galaxies {cz 4000 km/s}. Most of the objects were discovered before maximum brightness, and have follow-up photometry and spectroscopy; they include some of the best-studied SNe to date. We propose to conduct a snapshot imaging survey of the sites of some of these nearby objects, to obtain late-time photometry that {through the shape of the light and color curves} will help reveal the origin of their lingering energy. The images will also provide high- resolution information on the local environment of SNe that are far superior to what we can procure from the ground. For example, we will obtain color-color and color-magnitude diagrams of stars in these SN sites, to determine their progenitor masses and constraints on the reddening. Recovery of the SNe in the new HST images will also allow us to actually pinpoint their progenitor stars in cases where pre-explosion images exist in the HST archive. Use of ACS rather than WFPC2 will make our snapshot survey even more valuable than our Cycle 9 survey. This Proposal is complementary to our Cycle 13 archival proposal, in which we outline a plan for using existing HST images to glean information about SN environments. ACS/WFC/WFPC2 10265 The Formation History of Andromeda We propose deep observations of Andromeda's outer disk and giant tidal stream, to reconstruct their star formation histories. As the nearest giant galaxy, Andromeda offers the best testing ground for understanding galaxy formation and evolution. Given the dramatic increase in sensitivity offered by the ACS, we can now resolve stars on the old main sequence in the other giant spiral of the Local Group, and employ the same direct age diagnostics that have been used for decades in the study of Galactic globular clusters. In Cycle 11, we successfully observed a field in the Andromeda halo and constructed a deep color-magnitude diagram reaching well below the oldest main sequence turnoff. In Cycle 13, we propose to extend these observations to the outer disk and tidal stream of Andromeda, to constrain their star formation histories and compare them to that of the halo. The combined observations from these two programs will offer a dramatic advance in our understanding of the overall evolution of spiral galaxies. ACS/HRC 10253 A UV Survey of Quiescent Black Holes and Neutron Stars Existing STIS observations of quiescent Galactic black hole and neutron star binaries suggest a striking difference between them. The spectra of black holes appear to drop off steeply in the near-UV, whereas those of neutron stars continue to rise, at least down to 1700A. This difference has been interpreted in terms of advective accretion models, and may indicate a fundamental signature of the two types of object. The existing data do not include enough objects to form a representative sample, however. We will exploit the faint source sensitivity of ACS to perform a survey of the UV spectral shapes across a larger sample containing both black holes and neutron stars. This survey will test the assertion that their UV spectra are strikingly different; allow modelling of the broad band spectral energy distribution; test for variability in the UV flux; and identify suitable targets for subsequent spectroscopic follow-up.. ACS/WFC 10252 Improving the Astrometric Calibration of ACS/WFC for the Most Useful Filters The distortion correction for the WFC, with which most ACS astrometry is done, is filter- dependent, and is not sufficiently accurate for the most useful filters to the community, F606W and F814W. We propose to derive improved corrections using 1 orbit for each filter. A by-product will be an astrometric standard field at the center of Omega Centauri. ACS/WFC 10237 Low-Ionization BALs: Evolution or Orientation? We propose to test the hypothesis that Low-Ionization Broad Absorption Line Quasars {LoBALs} represent a special stage of quasar evolution: young quasars in systems with strong interaction and star-formation. We will carry out high resolution imaging using ACS/WFC and NICMOS to measure the properties of the host galaxies of four LoBAL quasars at z = 0.9 - 2.0 that show strong overlapping FeII absorption troughs. The ACS imaging will be carried out in the passband with the strongest BAL absorption, acting as a natural coronagraph. This results in a reduction of quasar light by a factor of 15 - 26 in these passbands, providing arguably the best view of the host galaxies of luminous, high-redshift quasars. This method allows efficient detection and detailed modeling of the host galaxy morphology in the rest-frame ultraviolet, which is most sensitive to star formation and galaxy interaction. We will also use NICMOS imaging to measure the rest- frame light from the host galaxy to probe the old stellar populations where the host galaxy is likely to be brighter. It has been suggested that LoBALs might not be explained simply as an orientation effect but rather as an early phase of quasar evolution. Such a phase is typically associated with large amounts of dust and gas, and young galaxies with strong star formation. With HST observations, we will study the color and morphology of the FeLoBAL quasar host galaxies, and measure the age of their dominant stellar populations. We will also measure the density of close companions, and, in particular, look for signs of ongoing or recent mergers. These measurements will be compared to those of control samples of normal quasars at similar redshift. If LoBALs are indeed young systems, then their host galaxies are expected to show stronger interactions and merger activity, younger stellar ages, and regions with strong star formation. If the LoBAL host galaxies show no significant difference from those of normal quasars, it will support the view that LoBAL quasars are not a distinct population and that all quasars have BAL outflows along some lines of sight. ACS/HRC 10199 The Most Massive Galaxies in the Universe: Double Trouble? We are proposing an HST snapshot survey of 70 objects with velocity dispersion larger than 350 km/s, selected from the Sloan Digital Sky Survey. Potentially this sample contains the most massive galaxies in the Universe. Some of these objects may be superpositions; HST imaging is the key to determining if they are single and massive or if they are two objects in projection. The objects which HST imaging shows to be single objects are interesting because they potentially harbor the most massive black holes, and because their existence places strong constraints on galaxy formation models. When combined with ground based data already in hand, the objects which HST imaging shows are superpositions provide valuable information about interaction rates of early- type galaxies as well as their dust content. They also constrain the allowed parameter space for models of binary gravitational lenses {such models are currently invoked to explain discrepancies in the distribution of lensed image flux ratios and separations}. ACS/HRC 10185 When does Bipolarity Impose itself on the Extreme Mass Outflows from AGB Stars? An ACS SNAPshot Survey Essentially all well-characterized preplanetary nebulae {PPNe} -- objects in transition between the AGB and planetary nebula evolutionary phases - are bipolar, whereas the mass-loss envelopes of AGB stars are strikingly spherical. In order to understand the processes leading to bipolar mass-ejection, we need to know at what stage of stellar evolution does bipolarity in the mass-loss first manifest itself? Our previous SNAPshot surveys of a PPNe sample {with ACS & NICMOS} show that roughly half our targets observed are resolved, with well-defined bipolar or multipolar morphologies. Spectroscopic surveys of our sample confirm that these objects have not yet evolved into planetary nebulae. Thus, the transformation from spherical to aspherical geometries has already fully developed by the time these dying stars have become preplanetary nebulae. From this new and surprising result, we hypothesize that the transformation to bipolarity begins during the very late AGB phase, and happens very quickly, just before, or as the stars are evolving off the AGB. We propose to test this hypothesis quantitatively, through a SNAPshot imaging survey of very evolved AGB stars which we believe are nascent preplanetary nebulae; with our target list being drawn from published lists of AGB stars with detected heavy mass-loss {from millimeter-wave observations}. This survey is crucial for determining how and when the bipolar geometry asserts itself. Supporting kinematic observations using long-slit optical spectroscopy {with the Keck}, millimeter and radio interferometric observations {with OVRO, VLA & VLBA} are being undertaken. The results from this survey {together with our previous work} will allow us to draw general conclusions about the onset of bipolar mass-ejection during late stellar evolution, and will provide crucial input for theories of post-AGB stellar evolution. Our survey will produce an archival legacy of long-standing value for future studies of dying stars. NIC2 10173 Infrared Snapshots of 3CR Radio Galaxies Radio galaxies are an important class of extragalactic objects: they are one of the most energetic astrophysical phenomena and they provide an exceptional probe of the evolving Universe, lying typically in high density regions but well-represented across a wide redshift range. In earlier Cycles we carried out extensive HST observations of the 3CR sources in order to acquire a complete and quantitative inventory of the structure, contents and evolution of these important objects. Amongst the results, we discovered new optical jets, dust lanes, face-on disks with optical jets, and revealed point-like nuclei whose properties support FR-I/BL Lac unified schemes. Here, we propose to obtain NICMOS infrared images of 3CR sources with z0.3 as a major enhancement to an already superb dataset. We aim to deshroud dusty galaxies, study the underlying host galaxy free from the distorting effects of dust, locate hidden regions of star formation and establish the physical characteristics of the dust itself. We will measure frequency and spectral energy distributions of point-like nuclei, expected to be stronger and more prevalent in the IR, seek spectral turnovers in known synchrotron jets and find new jets. We will strongly test unified AGN schemes and merge these data with existing X-ray to radio observations. The resulting database will be an incredibly valuable resource to the astronomical community for years to come. ACS/SBC 10125 Where is the Wind in 1H0707-495? We propose three observations using the narrow-line Seyfert 1 galaxy 1H 0707-495 to be coordinated with already-approved deep exposures using FUSE. A previous HST observation of 1H 0707-495 revealed strongly blueshifted high-ionization lines, suggesting an origin in an outflowing wind. Detailed photoionization modeling reveals that the wind line fluxes and ratios are consistent with two solutions: a high-density, high- column solution, originating close to the central engine, and a low-density, low-column solution, located much further out. These two locations, interestingly, correspond to those predicted by two different physical models for winds in AGNs. We can differentiate between these models by observing emission line variability on two time scales, and examining relative variability of OVI obtained by FUSE and CIV and other lines obtained by HST. We will also look for profile variability, constrain velocity ionization stratification through a detailed study of the profiles, and investigate metallicity, which has been suggested to be high in NLS1s. This program, requiring only a modest amount of time, is expected to make significant contributions to our understanding of outflows in AGN, and the structure, origin and metallicity of the broad- line region. ACS/WFC/WFPC2 10092 The COSMOS 2-Degree ACS Survey We will undertake a 2 square degree imaging survey {Cosmic Evolution Survey -- COSMOS} with ACS in the I {F814W} band of the VIMOS equatorial field. This wide field survey is essential to understand the interplay between Large Scale Structure {LSS} evolution and the formation of galaxies, dark matter and AGNs and is the one region of parameter space completely unexplored at present by HST. The equatorial field was selected for its accessibility to all ground-based telescopes and low IR background and because it will eventually contain ~100, 000 galaxy spectra from the VLT-VIMOS instrument. The imaging will detect over 2 million objects with I 27 mag {AB, 10 sigma}, over 35, 000 Lyman Break Galaxies {LBGs} and extremely red galaxies out to z ~ 5. COSMOS is the only HST project specifically designed to probe the formation and evolution of structures ranging from galaxies up to Coma-size clusters in the epoch of peak galaxy, AGN, star and cluster formation {z ~0.5 to 3}. The size of the largest structures necessitate the 2 degree field. Our team is committed to the assembly of several public ancillary datasets including the optical spectra, deep XMM and VLA imaging, ground-based optical/IR imaging, UV imaging from GALEX and IR data from SIRTF. Combining the full-spectrum multiwavelength imaging and spectroscopic coverage with ACS sub-kpc resolution, COSMOS will be Hubble's ultimate legacy for understanding the evolution of both the visible and dark universe. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTAR 9625: During LOS , FHST Update U2,3FM scheduled @ 345/22:07:40Z resulted in Error Box results failure indicating "2 FAILED". One 486 Status Buffer 901 message was observed. Subsequent GS Acquisition (1,2,1) passed. Under investigation. HSTAR 9627: During ZOE, GS Acquisition @ 347/17:02:39Z failed due to SRLE on FGS 2 and 3. FHST Updates @ 347/16:56Z showed error of 94.341, 420, and -28.474 and 0.001, 1.524, and 1.918 arcsec. FHST Map @ 347/17:10Z was occulted when exited ZOE. Next GS Acquisition (2,3,2) @ 347/18:38:39Z was successful. Under investigation. COMPLETED OPS REQs: 17350-0 Restoration of TGS FHST Moving Target Limits @ 347/23:24z 17339-0 Three Gyro Command Generator Restoration @ 347/23:32:32z OPS NOTES EXECUTED: 1290-0 Adjust Recharge Ratio Limit for High Sun/Orbit Time @ 345/14:07z SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 36 35 See Hstar # 9627 FGS Reacq 16 16 FHST Update 58 57 See Hstar # 9625 LOSS of LOCK SIGNIFICANT EVENTS: At the completion of the Two Gyro Science (TGS) On-Orbit Test (OOT), Day 3 testing, the Vehicle Slew Command Generator must be returned to the pre-TGS OOT, Three Gyro values to correctly maintain RWA wheel speeds. Successfully restored Three Gyro Command Generator parameters @ 347/23:32Z (OR 17339 with attached script). Verified during first major vehicle maneuver. GS Acquisition @348/02:15Z was successful, wheel speeds and torques were nominal throughout maneuver. The TGS FHST Moving Target limits were modified to support previous TGS testing. Software modifications are planned to replace the need for the limits modifications, as such the previous limits need to be restored. The Rate Damping Mode limits do not need to be modified. Successfully restored FHST Moving Target Limits @ 347/23:24Z (OR 17350 with attached script). |
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