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Daily 3672
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3672 PERIOD COVERED: DOY 224 OBSERVATIONS SCHEDULED ACS/HRC 10130 Systemic Proper Motions of the Magellanic Clouds from Astrometry with ACS: II. Second Epoch Images We request second epoch observations with ACS of Magellanic Cloud fields centered on the 40 quasars in the LMC and SMC for which we have first epoch Cycle 11 data. The new data will determine the systemic proper motion of the Clouds. An extensive astrometric analysis of the first epoch data shows that follow-up observations with a two year baseline will allow us to measure the proper motion of the clouds to within 0.022 mas/year in each of the two orthogonal directions {assuming that we can image 25 quasars, i.e., with a realistic Snapshot Program completion rate}. The best weighted combination of all previous measurements has a seven times larger error than what we expect. We will determine the proper motion of the clouds with 2% accuracy. When combined with HI data for the Magellanic Stream this will constrain both the mass distribution in the Galactic Halo and theoretical models for the origin of the Magellanic Stream. Previous measurements are too crude for such constraints. Our data will provide by far the most accurate proper motion measurement for any Milky Way satellite. 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. 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. ACS/WFC 10174 Dark-matter halos and evolution of high-z early-type galaxies Gravitational lensing and stellar dynamics provide two complementary methods to determine the mass distribution and evolution of luminous and dark-matter in early-type {E/S0} galaxies. The combined study of stellar dynamics and gravitational lensing allows one to break degeneracies inherent to each method separately, providing a clean probe of the internal structure of massive galaxies. Since most lens galaxies are at redshifts z=0.1-1.0, they also provide the required look-back time to study their structural and stellar-population evolution. We recently analyzed 5 E/S0 lens galaxies between z=0.5 and 1.0, combining exquisite Hubble Space Telescope imaging data with kinematic data from ground-based Keck spectroscopy, placing the first precise constraints on the dark-matter mass fraction and its inner slope beyond the local Universe. To expand the sample to ~30 systems -- required to study potential trends and evolution in the E/S0 mass profiles -- we propose to target the 49 E/S0 lens-galaxy candidates discovered by Bolton et al. {2004} from the Sloan Digital Sky Survey {SDSS}. With the average lens rate being 40% and some systems having a lensing probability close to unity, we expect to discover ~20 strong gravitational lenses from the sample. This will triple the current sample of 9 E/S0 systems, with data in hand. With the sample of 30 systems, we will be able to determine the average slope of the dark-matter and total mass profile of E/S0 galaxies to 10% and 4% accuracy, respectively. If present, we can simultaneously detect 10% evolution in the total mass slope with 95% confidence. This will provide unprecedented constraints on E/S0 galaxies beyond the local Universe and allow a stringent test of their formation scenarios and the standard cosmological model. ACS/WFC 10216 Co-evolution of spheroids and black holes The masses of the giant black holes in galaxies are correlated with the luminosities, masses, and velocity dispersions of their host spheroids. This empirical connection of phenomena on widely different scales {from sub-parsec to kiloparsec} suggests that the evolution of a galaxy and its central black hole are closely linked. We propose to test various unified formation models, by measuring the cosmic evolution of the black hole/spheroid relations, back to z=0.37 {a lookback time of 4 Gyrs}. We will obtain 1-orbit ACS images of a sample of 20 Seyfert 1 galaxies, for which we already have extensive new ground-based measures of the black hole masses and the stellar velocity dispersions. HST resolution is required for accurate measurement of the nonstellar AGN continuum, and the luminosity and effective radius of the bulge of each host galaxy. This will complete the set of observables needed to map the co-evolution of spheroids and black-holes. The proposed sample is the minimum required to make the first measure of the black hole mass/bulge correlation and of the fundamental plane for active galaxies outside the local Universe. ACS/WFC 10260 The Most Massive Star Clusters: Supermassive Globular Clusters or Dwarf Galaxy Nuclei? Evidence is mounting that the most massive globular clusters, such as Omega Centauri and M31-G1, may be related to the recently discovered "Ultra-Compact Dwarfs" and the dense nuclei of dE, N galaxies. However, no systematic imaging investigation of these supermassive globular clusters -- at the level of Omega Cen and beyond -- has been done, and we do not know what fraction of them might bear the signatures {such as large effective radii or tidal tails} of having originated as dE nuclei. We propose to use the ACS/WFC to obtain deep images of 18 such clusters in NGC 5128 and M31, the two nearest rich globular cluster systems. These globulars are the richest star clusters that can be found in nature, the biggest of them reaching 10^7 Solar masses, and they are likely to represent the results of star formation under the densest and most extreme conditions known. Using the profiles of the clusters including their faint outer envelopes, we will carry out state-of-the-art dynamical modelling of their structures, and look for any clear evidence which would indicate that they are associated with stripped satellites. This study will build on our previous work with STIS and WFPC2 imaging designed to study the 'Fundamental Plane' of globular clusters. When our new work is combined with Archival WFPC2, STIS, and ACS material, we will also be able to construct the definitive mapping of the Fundamental Plane of globular clusters at its uppermost mass range, and confirm whether or not the UCD and dE, N objects occupy a different structural parameter space. FGS 10202 Resolving OB Binaries in the Carina Nebula, Resuming the Survey In March 2002 we carried out a small, high-angular resolution survey of some of the brightest OB stars in the Carina Nebula with FGS1r in an attempt to resolve binary systems which had thus far evaded detection by other techniques. Of 23 stars observed, 5 new OB binaries were discovered with component separations ranging from 0.015" to0.325". This yield over the spatial domain of FGS1r's angular resolution, coupled with published statistics of the incidence of OB stars in short-period spectroscopic, and long-period visual binaries suggests that the fraction of binarity or multiplicity among OB stars is near unity. Our unexpected resolution of the prototype O2 If* star HD 93129A as a 55 milli-arcsecond double is a case in point that great care must be exercised when one attemps to establish the IMF and upper-mass cuttoff at the high-mass end of the HR diagram. We propose to resume the survey to observe a larger, statistically meaningful sample of OB stars to establish a firm assessment of multiplicity at the high-mass end of the IMF in these clusters. We will also investigate the single-star/binary-star status of several astrophysically important, individual stars in order to enable a better understanding of the evolution of high-mass stars. 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 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. NIC2 9875 The Fundamental Plane of Massive Gas-Rich Mergers We propose deep NICMOS H-band imaging of a carefully selected sample of 33 luminous, late-stage galactic mergers. This program is part of a comprehensive investigation of the most luminous mergers in the nearby universe, the ultraluminous infrared galaxies {ULIGs}. The high-resolution HST images will complement an extensive set of ground-based data that include long-slit NIR spectra from a recently approved Large VLT Programme. This unique dataset will allow us to derive with unprecedented precision structural -and- kinematic parameters for a large unbiased sample of objects spanning the entire ULIG luminosity function. These data will refine the fundamental plane of massive gas-rich mergers and enable us to answer the following questions: {1} Do ultraluminous mergers form elliptical galaxies, and in particular, giant ellipticals? {2} Do ULIGs evolve into optically bright QSOs? The results from this detailed study of massive mergers in the local universe will be relevant to understanding galaxy formation and evolution at earlier epochs, and in particular, the dusty sub-mm population that accounts for more than half of the star formation at z 1. 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. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTAR 9510: FHST Roll Delay Update (U1,2RD) @ 224/10:02:12Z failed with Error Box results indicating "2FAILED" for mnemonics QEBSTFG0, QEBSTFG1, and QEBSTFG2. Prior FHST Mat @ 224/09:16:24Z showed 3-axis (RSS) error value ~ 9.00 arcsec. Subsequent GS Acquisition (1,2,2) @ 224/10:14:46Z was successful. Under investigation. COMPLETED OPS REQs: 17245-2 Battery 1 Capacity Test (complete thru step 17; High Rate Terminated/Low Rate begin) @ 223/2012z) OPS NOTES EXECUTED: None SCHEDULED SUCCESSFUL FAILURE TIMES FGS GSacq 16 16 FGS REacq 0 0 FHST Update 22 21 @224/1002 HSTAR#9510 LOSS of LOCK SIGNIFICANT EVENTS: Battery 1 Capacity Test continues, completed through Step 17, estimate reach 15.06 Volt discharge cut-off in early am. Continuous ESTR Engineering Coverage during Battery Capacity Test. HST VEST testing of Safe Mode Recovery procedures for Inertial Hold and Zero Gyro scheduled 225/10:00Z - 22:00Z with GDOC, HITT, SE, and VEST using CCS "D" String. The purpose of this testing is to verify Safe Mode Recovery procedures in the event of an HST safing event into Inertial Hold or Zero Gyro. |
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