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Daily Report 3618
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3618 PERIOD COVERED: DOYs 142-144 OBSERVATIONS SCHEDULED NIC1/NIC2/NIC3 9995 Photometric Stability This NICMOS calibration proposal carries out photometric monitoring observations during Cycle 12. The format of the program is identical to that of the Cycle 11 program 9639, except that the frequency has been reduced to bimonthly. ACS/WFC/HRC 9977 Gravitational Microlensing in the NGC 3314A-B Galaxy Pair Determining the composition of the dark matter that dominates the masses of galaxies is an important unsolved problem, and the results of the MACHO Collaboration suggest that some of Milky Way's dark matter may be in the form of very old white dwarfs. However, some have argued that the excess of microlensing events seen by MACHO are due to a larger than expected microlensing rate for lens stars in the LMC itself or its tidal debris. We propose to address this question by detecting microlensing events in the line-of-sight galaxy pair NGC 3314 A & B. The large line-of-sight distance between these galaxies gives an optical depth that is 3-4 orders of magnitude larger than if the source stars and lenses were in the same galaxy, and the fact that the background galaxy is a spiral ensures that there will be a sufficient number of bright, non-variable source stars. Our proposed observations should have the sensitivity to detect microlensing by both ordinary stars and dark matter in NGC 3314A {the foreground galaxy}. If there are dark matter microlensing events to be found, they can be clearly distinguished from stellar microlensing events because they will occur outside the visible disk of NGC 3314A. If baryonic dark matter is detected in NGC 3314A, we will be able to map its radial density variation. FGS 9972 Calibrating the Mass-Luminosity Relation at the End of the Main Sequence We propose to use HST-FGS1R to calibrate the mass-luminosity relation {MLR} for stars less massive than 0.2 Msun, with special emphasis on objects near the stellar/brown dwarf border. Our goals are to determine M_V values to 0.05 magnitude, masses to 5 than double the number of objects with masses determined to be less than 0.20 Msun. This program uses the combination of HST-FGS3/FGS1R at optical wavelengths and ground-based infrared interferometry to examine nearby, subarcsecond binary systems. As a result of these measurements, we are deriving high quality luminosities and masses for the components in the observed systems, and characterizing their spectral energy distributions from 0.5 to 2.2 Mum. Several of the objects included have M 0.1 Msun, placing them at the very end of the stellar main sequence. Three of the targets are brown dwarf candidates, including the current low mass record holder, GJ 1245C, with a mass of 0.062 +/- 0.004 Msun. The payoff of this proposal is high because all 10 of the systems selected have already been resolved with HST- FGS3/FGS1R during Cycles 5--10 and contain most of the reddest objects for which masses can be determined. STIS/CCD/MA1 9874 Probing IGM Phases, Metals, and the Cosmic Web with New SDSS QSOs We propose STIS G140L SNAPSHOT observations of 100 new z 1 QSOs from the Sloan Digital Sky Survey for studies of the IGM. These targets will be chosen to simultaneously maximize IGM pathlength and to form closely spaced groups of 2-8 QSO sightlines within 1 h^-1 Mpc of a foreground galaxy. These observations will, in the long term, provide a rich database of target QSOs for detailed study by COS of the IGM phases, metallicity, and relationship to the large scale structure. In the near term, these observations will detect up to 10 Lyman alpha clouds with N_HI 10^14 and 3 clouds with N_HI 10^15, per target. Thus they will provide an immediate test of filamentary structure in the "cosmic web" within 1 h^-1 Mpc of galaxies. We ask for 22 minute exposures for each target with STIS/G140L to obtain S/N = 5-16 for these V = 16 - 18 QSOs. These observations will be sensitive to Lyman alpha equivalent widths ranging from 300 mA for the brighter sources to 600 mA at the fainter end. These targets represent a Deltaz pathlength of 17 {at 50% yield}, with Deltaz = 10 in the range where Lya, Lyb, and O VI lie in the HST band. These observations will also refine predictions of the FUV flux of QSOs based on the larger SDSS sample and will estimate the degree to which such factors as intrinsic and Galactic extinction, variability, and intervening absorption can be controlled. If successful, this technique could make UV-prequalification SNAPs of QSOs obsolete, at a significant savings of HST time. Our observations lie at the median duration for SNAPs, and in the range most likely to be executed. Our program accomplishes both near- and long-term goals at a relatively low investment of time, and thus is ideally suited for a SNAP proposal. To ensure maximum scientific return for our own purposes and for additional science {HVCs, Galactic halo} we waive the right to a proprietary data period. NIC/NIC3 9865 The NICMOS Parallel Observing Program We propose to continue managing the NICMOS pure parallel program. Based on our experience, we are well prepared to make optimal use of the parallel opportunities. The improved sensitivity and efficiency of our observations will substantially increase the number of line-emitting galaxies detected. As our previous work has demonstrated, the most frequently detected line is Halpha at 0.7z1.9, which provides an excellent measure of current star formation rate. We will also detect star-forming and active galaxies in other redshift ranges using other emission lines. The grism observations will produce by far the best available Halpha luminosity functions over the crucial--but poorly observed--redshift range where galaxies appear to have assembled most of their stellar mass. This key process of galaxy evolution needs to be studied with IR data; we found that observations at shorter wavelengths appear to have missed a large fraction of the star-formation in galaxies, due to dust reddening. We will also obtain deep F110W and F160W images, to examine the space densities and morphologies of faint red galaxies. In addition to carrying out the public parallels, we will make the fully reduced and calibrated images and spectra available on-line, with some ground-based data for the deepest parallel fields included. ACS/WFC 9860 ESSENCE: Measuring the Dark Energy Equation of State The accelerating universe appears to be dominated by a dark energy with a significant negative pressure. The ratio of the pressure to density of this mysterious energy {its equation of state} is an observable which can differentiate between the proliferating candidate theories. We propose to estimate the dark energy equation of state by observing Type Ia supernovae at redshifts near z=0.7 with HST in concert with the on-going ESSENCE NOAO Survey program that is discovering and studying supernovae between 0.3z0.8. We show that an interesting constraint on the equation of state can be made with supernovae observed at modest redshifts given the current knowledge of the matter density. We will follow 10 Type Ia supernovae discovered from the ground and passed to HST without disrupting its schedule. The full data set will constrain the equation of state to 10% and strictly limit the range of possible dark energy models. In keeping with the ESSENCE policy, these observations will available to the community immediately. NIC1 9833 T Dwarf Companions: Searching for the Coldest Brown Dwarfs Faint companions to known stars have historically led to the discovery of new classes of stellar and substellar objects. Because these discoveries are typically limited by the flux ratio of the components in the system, the intrinsically faintest companions are most effectively identified around the intrinsically faintest primaries. We propose to use NICMOS to image a sample of 22 of the coolest known {T-type} brown dwarfs in the Solar Neighborhood in order to search for fainter and cooler brown dwarf companions. The high spatial resolution of the NIC 1 detector enables us to distinguish binary systems with apparent separations greater than 0"08, or physical separations greater than 1.2 AU at the nominal distances of the objects in our sample. Furthermore, the substantial sensitivity of NICMOS imaging allows us to probe companion masses of 5-50 Jupiter masses and companion effective temperatures of 250-1300 K in a maximally efficient manner. Based on work to date, we expect that roughly 20% of the objects in our sample will be binary, and that one or two of these will likely harbor a significantly fainter secondary. Hence, we expect to find a companion cooler than any currently known brown dwarf, a potential prototype for the next spectral class. In addition, our investigation will add substantially to the sample of known binary brown dwarfs, allowing improved statistical analyses of the binary fraction, separation distribution, and mass ratio distribution of these systems, key quantities for probing brown dwarf formation. We will also identify optimal substellar systems for astrometric mass measurements, a critical check for theoretical models of brown dwarfs and extrasolar planets. STIS/CCD/MA1/MA2 9827 UV extinction by dust in unexplored LMC environments The ensemble of results from studies of the UV extinction in the Milky Way, Magellanic Clouds {MC}, M31 and M33, indicates a complex dependence of the dust properties with environment, where starburst activity and metallicity are relevant factors. Work in the LMC to date, based on IUE data, has several drawbacks: a} only supergiants could be used, b} they all have moderate extinction, c} the IUE S/N is limited, d} the large IUE slit may include light from other sources, such as scattered light from dust or faint companion stars, e} studies are confined to few {extreme} environments. We propose to obtain UV extinction curves more accurate than previous ones {from STIS spectra of main sequence stars with higher reddening}, sampling four environments in the LMC with different levels of star formation activity, including the general field, hitherto unexplored. The results will characterize the properties of dust in different conditions, at the LMC metallicity, which is useful to intepret integrated properties of distant galaxies, as well as GALEX upcoming UV surveys. A complementary study is under way with FUSE in the far-UV range. The combined results will provide insight on the properties of small grains. NIC3 9824 NIC3 SNAPs of nearby galaxies imaged in the mid-UV: the remarkable cool stellar population in late-type galaxies. We propose a NIC3 H-band {F160W} SNAPshot survey of 48 nearby mid- to late-type galaxies covering all inclinations. In Cycle 9 and 10, we imaged ~100 galaxies in the mid-UV {F300W/F255W} and I-band {F814W} with WFPC2, and obtained UBVR CCD surface photometry from the ground. Early-mid-type galaxies show the usual small radial color-gradients, where disks become somewhat bluer at larger radii. But, remarkably, the majority of {lower luminosity, smaller and rounder} late-type galaxies shows the opposite trend and becomes redder outwards in all filters. While young UV/blue-bright stellar populations dominate their inner morphology, most late-type galaxies must have a significant halo or thick disk of older stars. Combining our proposed NIC3 H-band with existing WFPC2 images will span the wavelength range 0.29-1.6 micron at resolutions of 0.04-0.16" {FWHM}. This Panchromatic Nearby Galaxy Atlas will be applicable to a wide range of problems, and will be made public immediately. Our NIC3/F160W science goals are to: {1} Establish the nature of the old outer stellar population. All target galaxies have z0.005, allowing us to resolve any luminous, cool supergiant population. NIC3 is essential to make a pixel-to-pixel color-magnitude study of the nature, distribution and uniformity of the outer stellar populations, which will constrain dwarf galaxy formation theories. {2} Determine galaxy structure at 5-20 pc resolution, tracing the old stellar population and mass distribution compared to the star-forming regions seen in the mid-UV. A range of inclinations is needed to distinguish between old thick disks or halos in late-type galaxies. {3} Make a multi-wavelength pixel-to-pixel decomposition to help delineate the effects of dust, age, and metallicity. Since we must cover a range of inclinations, NIC3 H-band is essential to map the effects from dust, and see how these may affect the studies of {1} and {2}. ACS/WFC 9788 A Narrow-band Snapshot Survey of Nearby Galaxies We propose to use ACS/WFC to conduct the first comprehensive HST narrow-band {H-alpha + [N II]} imaging survey of the central regions of nearby bulge-dominated disk {S0 to Sbc} galaxies. This survey will cover, at high angular resolution extending over a large field, an unprecedented number of galaxies representing many different environments. It will have important applications for many astrophysical problems of current interest, and it will be an invaluable addition to the HST legacy. The observations will be conducted in snapshot mode, drawing targets from a complete sample of 145 galaxies selected from the Palomar spectroscopic survey of nearby galaxies. Our group will use the data for two primary applications. First, we will search for nuclear emission-line disks suitable for future kinematic measurements with STIS, in order to better constrain the recently discovered relations between black hole mass and bulge properties. Preliminary imaging of the type proposed here must be done, sooner or later, if we are to make progress in this exciting new field. Second, we will investigate a number of issues related to extragalactic star formation. Specifically, we will systematically characterize the properties of H II regions and super star clusters on all galactic scales, from circumnuclear regions to the large-scale disk. 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. ACS/HRC/WFC 9763 Calibrating the Black Hole Mass Scale for Quasars We propose to obtain ACS/WFC imaging of all 17 low-redshift quasars that have black hole masses measured from reverberation mapping. This is a key sample since all secondary methods to estimate black hole mass in quasars depend on this local reverberation-mapped sample for their calibration. The best external check on reverberation mapping is whether it gives results that are consistent with the black hole mass- host galaxy correlations of nearby galaxies. For local Seyfert galaxies the reverberation masses appear consistent with the M-sigma correlation, but it is not known whether this also holds true for quasars because the stellar velocity dispersions of quasar hosts are virtually impossible to measure. We will use the ACS data to measure accurate bulge parameters {luminosity and effective radius} for the host galaxies of the reverberation-mapped quasars. From the fundamental plane or the Faber-Jackson relation, we can estimate the host galaxy velocity dispersion and test whether the reverberation masses follow the M-sigma relation even for objects with quasar luminosities. This is a crucial test if we are to trust the reverberation masses as the lowest rung on a "distance ladder" of black hole mass estimators for quasars, so that quasars can be used to trace the cosmological growth history of black holes. {Note added in Phase II: the TAC awarded us 8 orbits to observe 7 quasars and a PSF star.} ACS/HRC/WFC 9728 Tracing the History of Cosmic Expansion to z~2 with Type Ia Supernovae Type Ia supernovae {SNe Ia} provide the only direct evidence for an accelerating universe, an extraordinary result that needs the most rigorous test. The case for cosmic acceleration rests on the observation that SNe Ia at z = 0.5 are about 0.25 mag fainter than they would be in a universe without acceleration. A powerful and straightforward way to assess the reliability of the SN Ia measurement and the conceptual framework of its interpretation is to look for cosmic deceleration at z 1. This would be a clear signature of a mixed dark-matter and dark-energy universe. Systematic errors in the SNe Ia result attributed to grey dust or cosmic evolution of the SN Ia peak luminosity would not show this change of sign. We have obtained a toehold on this putative ``epoch of deceleration'' with SN 1997ff at z = 1.7, and 3 more at z 1 from our Cycle 11 program, all found and followed by HST. However, this is too important a test to rest on just a few objects, anyone of which could be subject to a lensed line-of-sight or misidentification. Here we propose to extend our measurement with observations of twelve SNe Ia in the range 1.0 z 1.5 or 6 such SNe Ia and 1 ultradistant SN Ia at z = 2, that will be discovered as a byproduct from proposed Treasury and DD programs. These objects will provide a much firmer foundation for a conclusion that touches on important questions of fundamental physics. ACS/WFC 9727 Exploration of the SN Ia Hubble Diagram at z 1.2 In the spirit of a Treasury proposal, we propose to organize, and deliver to the astronomical community, non-proprietary follow-up observations of ~10 Type Ia supernovae at 1z1.7 that are expected to be discovered in a Cycle 12 Treasury proposal. Together with the currently available sample, this would provide a Hubble diagram with over 20 SNe Ia in this redshift range, where it is possible to test the current cosmological model in the epoch of deceleration: If z ~ 0.5 SNe Ia are fainter due to evolution rather than an accelerating expansion, they should continue to get fainter at even higher redshifts. This size sample will show trends and outliers, and permit a more rigorous treatment of the asymmetric amplification distribution from gravitational lensing. This is a key redshift range for the studies of dark energy that will be done with future surveys; this dataset will lay the ground-work for these studies by establishing the simple properties of the supernovae in this redshift range, including magnitudes, colors, and timescales. If considered more appropriate, this proposal could be treated as a part of a Treasury or Director's Discretionary program, since the data would be available to everybody immediately, and we would welcome others who would want to work with us on it. NICMOS/STIS CCD 9405 The Origin of Gamma-Ray Bursts The rapid and accurate localization of gamma-ray bursts {GRBs} promised by a working HETE-2 during the coming year may well revolutionize our ability to study these enigmatic, highly luminous transients. We propose a program of HST and Chandra observations to capitalize on this extraordinary opportunity. We will perform some of the most stringent tests yet of the standard model, in which GRBs represent collimated relativistic outflows from collapsing massive stars. NICMOS imaging and STIS CCD spectroscopy will detect broad atomic features of supernovae underlying GRB optical transients, at luminosities more than three times fainter than SN 1998bw. UV, optical, and X-ray spectroscopy will be used to study the local ISM around the GRB. Chandra spectroscopy will investigate whether the GRB X-ray lines are from metals freshly ripped from the stellar core by the GRB. HST and CTIO infra-red imaging of the GRBs and their hosts will be used to determine whether `dark' bursts are the product of unusually strong local extinction; imaging studies may for the first time locate the hosts of `short' GRBs. Our early polarimetry and late-time broadband imaging will further test physical models of the relativistic blast wave that produces the bright GRB afterglow, and will provide unique insight into the influence of the GRB environment on the afterglow. NIC1/NIC2/NIC3 8792 NICMOS Post-SAA calibration - CR Persistence Part 3 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. 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/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. WFPC2 10070 WFPC2 CYCLE 12 Supplemental Darks Part 2/3 This dark calibration program obtains 3 dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. ACS/HRC/WFC 10060 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 10046 CCD Hot Pixel Annealing Hot pixel annealing will be performed once every 4 weeks. The CCD TECs will be turned off and heaters will be activated to bring the detector temperatures to about +20C. This state will be held for approximately 12 hours, after which the heaters are turned off, the TECs turned on, and the CCDs returned to normal operating condition. To assess the effectiveness of this procedure, a bias and two dark images will be taken after the annealing procedure for both WFC and HRC. The HRC darks are taken in parallel with the WFC darks. STIS/CCD 10037 STIS Cycle 12 Faint Standard Extension: FASTEX WD 1657+343 is the faintest of four pure hydrogen WD stars that comprised the original FASTEX program and has been observed thrice in 2000 and once in 2002 to firmly establish the absolute flux levels. Annual revisits of one orbit should occur to monitor our predictions of the CTE correction, which is increasing with time on orbit. G430L at both the standard and E1 aperture position are required at the exposure times already established as standard. The remaining time in the orbit will be spent extending the wavelength coverage using G750L. To date, HST has not provided any faint solar analog stars to compliment the three V=12-13.5 mag solar analogs provided by M. Rieke for NICMOS calibration. As instrumentation in space and on the ground becomes more sensitive, fainter flux standards are required. A solar analog in a field with low reddening is an excellent choice for a fainter standard, because unreddened pure hydrogen WDs are rare beyond V=16, because Solar absolute fluxes are well measured at all wavelengths, and because the fluxes do not fall off as fast as the hot WDs at longer wavelengths. A 16.5 G star may not be faint enough for most JWST modes but will provide a significant step in the right direction. The SNAP program requires such a spectrophotometric standard, which lies at the bright limit of its spectroscopy mode. NICMOS grism observation of this standard are planned for cycle 12 and STIS spectra are required to establish the standard over the full range from 0.3-2 microns. 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.) HSTAR 9421: GS Acquisition (1,2,1) @ 142/22:24:24Z ended in FL backup on FGS 1 due to SSLE on FGS 2 @ 142/22:28:31Z. Under investigation. HSTAR 9422: During ZOE, GS Acquisition (2,1,1) scheduled @ 143/10:39:19Z resulted in FL backup on FGS 2. At AOS @ 143/10:53:34Z, there were no flags, however, only FGS 2 resulted in FL. Previous FHST FM Updates @ 143/10:22Z and 10:25Z both succeeded with low vehicle errors. Following FHST Map @ 143/11:17:01Z showed axis errors of 2.275, 5.927, and 1.199 arcsec. Under investigation. HSTAR 9423: GS Reacquisition (1,2,2) @ 144/12:03:38Z required two attempts to reach FL due to SSLE on FGS 2. Under investigation. COMPLETED OPS REQs: None OPS NOTES EXECUTED: 1234-0 TDW Cross-support tracking (T77 CODE)(Closed) 1236-0 Change Limits MAMA1 Threshold Voltage @ 143/0621z (closed) 1224-2 Bay 5 Web Temp Limit Changed @143/1151z (closed) SCHEDULED SUCCESSFUL FAILURE TIMES FGS GSacq 33 33 FGS REacq 15 15 FHST Update 53 53 LOSS of LOCK SIGNIFICANT EVENTS: Gyro Scale Factor modification SMS SA145. Modified value is: rga_scale_error = ¼"/degree. |
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