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Daily Report # 4321
Notice: For the foreseeable future, the daily reports may contain
apparent discrepancies between some proposal descriptions and the listed instrument usage. This is due to the conversion of previously approved ACS WFC or HRC observations into WFPC2, or NICMOS observations subsequent to the loss of ACS CCD science capability in late January. HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science DAILY REPORT # 4321 PERIOD COVERED: UT March 16,17,18, 2007 (DOY 075,076,077) OBSERVATIONS SCHEDULED NIC1/NIC2/NIC3 8795 NICMOS Post-SAA calibration - CR Persistence Part 6 A new proceedure proposed to alleviate the CR-persistence problem of NICMOS. Dark frames will be obtained immediately upon exiting the SAA contour 23, and everytime 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 i mages. Each observation will need its own CRMAP, as different SAA passages leave different imprints on the NICMOS detectors. NIC3 11080 Exploring the Scaling Laws of Star Formation As a variety of surveys of the local and distant Universe are approaching a full census of galaxy populations, our attention needs to turn towards understanding and quantifying the physical mechanisms that trigger and regulate the large-scale star formation rates {SFRs} in galaxies. ACS/SBC 11074 ACS/SBC Darks in Support of Specific SBC Science Observations This program provides SBC DARK visits to be scheduled in conjuction with certain specific science observations which require the SBC to be turned on in the orbit preceeding the science observation. ACS/SBC 11050 ACS UV contamination monitor The observations consist of imaging and spectroscopy with SBC of the cluster NGC 6681 in order to monitor the temporal evolution of the UV sensitivity of the SBC. FGS 10989 Astrometric Masses of Extrasolar Planets and Brown Dwarfs We propose observations with HST/FGS to estimate the astrometric elements {perturbation orbit semi-major axis and inclination} of extra-solar planets orbiting six stars. These companions were originally detected by radial velocity techniques. We have demonstrated that FGS astrometry of even a short segment of reflex motion, when combined with extensive radial velocity information, can yield useful inclination information {McArthur et al. 2004}, allowing us to determine companion masses. Extrasolar planet masses assist in two ongoing research frontiers. First, they provide useful boundary conditions for models of planetary formation and evolution of planetary systems. Second, knowing that a star in fact has a plantary mass companion, increases the value of that system to future extrasolar planet observation missions such as SIM PlanetQuest, TPF, and GAIA. NIC2 10906 The Fundamental Plane of Massive Gas-Rich Mergers: II. The QUEST QSOs We propose deep NICMOS H-band imaging of a carefully selected sample of 23 local QSOs. This program is the last critical element of a comprehensive investigation of the most luminous mergers in the nearby universe, the ultraluminous infrared galaxies {ULIRGs} and the quasars. This effort is called QUEST: Quasar / ULIRG Evolutionary STudy. The high-resolution HST images of the QUEST QSOs will complement an identical set of images on the ULIRG sample obtained during Cycle 12, an extensive set of ground-based data that include long-slit NIR spectra from a Large VLT Program, and a large set of mid-infrared spectra from a Cycle 1 medium-size program with Spitzer. This unique dataset will allow us to derive with unprecedented precision structual, kinematic, and activity parameters for a large unbiased sample of objects spanning the entire ULIRG/QSO luminosity function. These data will refine the fundamental plane of massive gas-rich mergers and enable us to answer the following quesitons: {1} Do ultraluminous mergers form elliptical galaxies, and in particular, giant ellipticals? {2} Do ULIRGs evolve into optical bright QSOs? The results from this detailed study of massive mergers in the local universe will be relevant to understanding the basic physical processes involved in creating massive early-type host on the one hand, and growing/feeding embedded massive black holes on the other, in major galaxy mergers. This is an important question since 50% of cosmic star formation at high-z and most of the big BHs appear to be formed in this process. WFPC2 10890 Morphologies of the Most Extreme High-Redshift Mid-IR-Luminous Galaxies The formative phase of the most massive galaxies may be extremely luminous, characterized by intense star- and AGN-formation. Till now, few such galaxies have been unambiguously identified at high redshift, restricting us to the study of low-redshift ultraluminous infrared galaxies as possible analogs. We have recently discovered a sample of objects which may indeed represent this early phase in galaxy formation, and are undertaking an extensive multiwavelength study of this population. These objects are bright at mid-IR wavelengths {F[24um]0.8mJy}, but deep ground based imaging suggests extremely faint {and in some cases extended} optical counterparts {R~24-27}. Deep K- band images show barely resolved galaxies. Mid-infrared spectroscopy with Spitzer/IRS reveals that they have redshifts z ~ 2-2.5, suggesting bolometric luminosities ~10^{13- 14}Lsun! We propose to obtain deep ACS F814W and NIC2 F160W images of these sources and their environs in order to determine kpc-scale morphologies and surface photometry for these galaxies. The proposed observations will help us determine whether these extreme objects are merging systems, massive obscured starbursts {with obscuration on kpc scales!} or very reddened {locally obscured} AGN hosted by intrinsically low-luminosity galaxies. ACS/SBC 10862 Comprehensive Auroral Imaging of Jupiter and Saturn during the International Heliophysical Year A comprehensive set of observations of the auroral emissions from Jupiter and Saturn is proposed for the International Heliophysical Year in 2007, a unique period of especially concentrated measurements of space physics phenomena throughout the solar system. We propose to determine the physical relationship of the various auroral processes at Jupiter and Saturn with conditions in the solar wind at each planet. This can be accomplished with campaigns of observations, with a sampling interval not to exceed one day, covering at least one solar rotation. The solar wind plasma density approaching Jupiter will be measured by the New Horizons spacecraft, and a separate campaign near opposition in May 2007 will determine the effect of large-scale variations in the interplanetary magnetic field {IMF} on the Jovian aurora by extrapolation from near-Earth solar wind measurements. A similar Saturn campaign near opposition in Jan. 2007 will combine extrapolated solar wind data with measurements from a wide range of locations within the Saturn magnetosphere by Cassini. In the course of making these observations, it will be possible to fully map the auroral footprints of Io and the other satellites to determine both the local magnetic field geometry and the controlling factors in the electromagnetic interaction of each satellite with the corotating magnetic field and plasma density. Also in the course of making these observations, the auroral emission properties will be compared with the properties of the near-IR ionospheric emissions {from ground- based observations} and non thermal radio emissions, from ground-based observations for Jupiter?s decametric radiation and Cassini plasma wave measurements of the Saturn Kilometric Radiation {SKR}. WFPC2 10815 The Blue Hook Populations of Massive Globular Clusters Blue hook stars are a class of hot {~35,000 K} subluminous horizontal branch stars that have been recently discovered using HST ultraviolet images of the globular clusters omega Cen and NGC 2808. These stars occupy a region of the HR diagram that is unexplained by canonical stellar evolution theory. Using new theoretical evolutionary and atmospheric models, we have shown that the blue hook stars are very likely the progeny of stars that undergo extensive internal mixing during a late helium core flash on the white dwarf cooling curve. This "flash mixing" produces an enormous enhancement of the surface helium and carbon abundances, which suppresses the flux in the far ultraviolet. Although flash mixing is more likely to occur in stars that are born with high helium abundances, a high helium abundance, by itself, does not explain the presence of a blue hook population - flash mixing of the envelope is required. We propose ACS ultraviolet {SBC/F150LP and HRC/F250W} observations of the five additional globular clusters for which the presence of blue hook stars is suspected from longer wavelength observations. Like omega Cen and NGC 2808, these five targets are also among the most massive globular clusters, because less massive clusters show no evidence for blue hook stars. Because our targets span 1.5 dex in metallicity, we will be able to test our prediction that flash-mixing should be less drastic in metal-rich blue hook stars. In addition, our observations will test the hypothesis that blue hook stars only form in globular clusters massive enough to retain the helium-enriched ejecta from the first stellar generation. If this hypothesis is correct, then our observations will yield important constraints on the chemical evolution and early formation history in globular clusters, as well as the role of helium self-enrichment in producing blue horizontal branch morphologies and multiple main sequence turnoffs. Finally, our observations will provide new insight into the formation of the hottest horizontal branch stars, with implications for the origin of the hot helium-rich subdwarfs in the Galactic field. NIC2 10808 Morphologies of spectroscopically-confirmed "red and dead" galaxies at z~2.5 Using a combination of wide-field near-infrared imaging and very deep follow-up near- infrared spectroscopy we have identified a population of massive "red and dead" galaxies at z~2.5. The galaxies lack emission lines and have strong Balmer/4000 Angstrom breaks, demonstrating directly that they have evolved stellar populations. These objects are very likely progenitors of massive ellipticals today and may be descendants of the first generation of galaxies. We propose to image 10 of these objects with the NIC2 camera to determine their morphologies. The goals are to 1} determine whether they have the sizes of present-day early-types or are more compact, as predicted by models, 2} determine the morphology, using visual classification and quantitative methods, and 3} constrain the evolution of the Kormendy relation from z~2.5 to the present. These observations will show whether the oldest and most massive galaxies at z~2.5 were already fully formed or still in the process of assembly. NIC2 10802 SHOES-Supernovae, HO, for the Equation of State of Dark energy The present uncertainty in the value of the Hubble constant {resulting in an uncertainty in Omega_M} and the paucity of Type Ia supernovae at redshifts exceeding 1 are now the leading obstacles to determining the nature of dark energy. We propose a single, integrated set of observations for Cycle 15 that will provide a 40% improvement in constraints on dark energy. This program will observe known Cepheids in six reliable hosts of Type Ia supernovae with NICMOS, reducing the uncertainty in H_0 by a factor of two because of the smaller dispersion along the instability strip, the diminished extinction, and the weaker metallicity dependence in the infrared. In parallel with ACS, at the same time the NICMOS observations are underway, we will discover and follow a sample of Type Ia supernovae at z 1. Together, these measurements, along with prior constraints from WMAP, will provide a great improvement in HST's ability to distinguish between a static, cosmological constant and dynamical dark energy. The Hubble Space Telescope is the only instrument in the world that can make these IR measurements of Cepheids beyond the Local Group, and it is the only telescope in the world that can be used to find and follow supernovae at z 1. Our program exploits both of these unique capabilities of HST to learn more about one of the greatest mysteries in science. NIC2 10798 Dark Halos and Substructure from Arcs & Einstein Rings The surface brightness distribution of extended gravitationally lensed arcs and Einstein rings contains super-resolved information about the lensed object, and, more excitingly, about the smooth and clumpy mass distribution of the lens galaxies. The source and lens information can non-parametrically be separated, resulting in a direct "gravitational image" of the inner mass-distribution of cosmologically-distant galaxies {Koopmans 2005; Koopmans et al. 2006 [astro-ph/0601628]}. With this goal in mind, we propose deep HST ACS-F555W/F814W and NICMOS-F160W WFC imaging of 20 new gravitational-lens systems with spatially resolved lensed sources, of the 35 new lens systems discovered by the Sloan Lens ACS Survey {Bolton et al. 2005} so far, 15 of which are being imaged in Cycle-14. Each system has been selected from the SDSS and confirmed in two time- efficient HST-ACS snapshot programs {cycle 13&14}. High-fidelity multi-color HST images are required {not delivered by the 420s snapshots} to isolate these lensed images {properly cleaned, dithered and extinction-corrected} from the lens galaxy surface brightness distribution, and apply our "gravitational maging" technique. Our sample of 35 early-type lens galaxies to date is by far the largest, still growing, and most uniformly selected. This minimizes selection biases and small-number statistics, compared to smaller, often serendipitously discovered, samples. Moreover, using the WFC provides information on the field around the lens, higher S/N and a better understood PSF, compared with the HRC, and one retains high spatial resolution through drizzling. The sample of galaxy mass distributions - determined through this method from the arcs and Einstein ring HST images - will be studied to: {i} measure the smooth mass distribution of the lens galaxies {dark and luminous mass are separated using the HST images and the stellar M/L values derived from a joint stellar-dynamical analysis of each system}; {ii} quantify statistically and individually the incidence of mass-substructure {with or without obvious luminous counter-parts such as dwarf galaxies}. Since dark-matter substructure could be more prevalent at higher redshift, both results provide a direct test of this prediction of the CDM hierarchical structure-formation model. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTARS: 10742 - GSACQ(1,2,1) failed, Search Radius Limit Exceeded on FGS 1 GSACQ(1,2,1) at 076/13:19:37 failed due to Search Radius Limit Exceeded on FGS 1 at 13:25:27. OBAD data prior to GSACQ showed RSS attitude correction of 6.27 arcseconds, OBAD map after GSACQ failure showed RSS error of 2.09 arcseconds. REACQ(1,2,1) at 14:52:52 also failed with search radius limit exceeded on FGS 1. All subsequent REACQ(1,2,1)s at 16:28:45, 18:04:39, 19:40:33 and 21:16:26 failed. 10744 - REAcq (1,2,1) failed due to Search Radius Limit Exceeded on FGS 1 At AOS 076/23:53:35, REAcq (1,2,1) scheduled from 22:53:02-23:00:25 had failed due to search radius limit exceeded on FGS 1. COMPLETED OPS REQUEST: (None) COMPLETED OPS NOTES: (None) SCHEDULED SUCCESSFUL FGS GSacq 22 21 FGS REacq 19 13 OBAD with Maneuver 80 80 SIGNIFICANT EVENTS: (None) |
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