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Daily 3843
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3843 PERIOD COVERED: DOY 110 OBSERVATIONS SCHEDULED ACS/HRC 10391 Wavelength and Flux Calibration of the ACS prisms The wavelength calibration of the SBC {PR110L and PR130L} and HRC {PR200L} prisms will be established by observing a planetary nebula in the LMC and QSOs at carefully selected redshifts. Flux calibrations will be derived for each prism by observing white dwarf standards. ACS/HRC 10435 Merger-Induced Populations in Early-Type Galaxy Cores Hierarchical formation models predict that early-type galaxies are built up over an extended period from mergers of smaller systems, a process which should leave long- lived signatures in their light profiles and stellar population colors. Merger events should have continued up to relatively recent times {the last 1-5 Gyr}, and many ellipticals and S0 bulges should therefore show evidence of multiple, discrete, intermediate-age populations. Although there is substantial observational support for a dissipational merger origin for some early-type galaxies, most do not exhibit the expected anomalies in either their light profiles or color distributions. However, existing searches {mainly in the V and I bands} have not probed very deeply. Here we propose high resolution, broad-band, near-ultraviolet {2500-3400 A} imaging of the cores of bright early-type galaxies. This is the most sensitive probe available for the detection of spatially-segregated, multiple population components with ages in the range 1-5 Gyr. Our sample consists of dust- and AGN-free systems with both normal and mildly anomalous central light profiles. There is very little existing information on the near-UV structure of early-type galaxies, and our program would effectively explore new terrain. ACS/HRC/WFC 10389 ACS CCDs daily monitor - Cycle 13 - Part 2 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. ACS/HRC/WFC 10436 Black Hole Growth and the Black Hole Mass -- Bulge Relations for AGNs Recent work has shown that the mass of a black hole is tightly correlated with the bulge mass of its host galaxy. This relation needs to be understood in the context of black hole growth in its active phase. Highly accreting AGNs, like narrow line Seyfert 1 galaxies {NLS1s}, are found to lie below the black hole mass -- bulge velocity dispersion correlation of normal galaxies and broad line AGNs. This result was obtained using FWHM{[OIII]} as a surrogate for the bulge velocity dispersion. To test this result we propose to obtain high resolution images of 10 NLS1s that do not lie on the black hole mass--sigma relation and measure accurate bulge parameters {luminosity and effective radius}. We will obtain an alternate handle on the bulge velocity dispersion through the fundamental plane relations and also find the locus of these NLS1s on the black hole mass--bulge luminosity plane. Testing this result is crucial to understanding the role of accretion on black hole growth, the observed correlations of the black hole mass with the bulge, and the formation and evolution of galaxies. 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 10369 ACS internal CTE monitor The charge transfer efficiency {CTE} of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be closely monitored at regular intervals, because it is likely to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets {lamps} only, so all of the exposures should be taken during Earth occultation time {but not during SAA passages}. This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing {program 8948}, so that results from each epoch can be directly compared. Extended Pixel Edge Response {EPER} and First Pixel Response {FPR} data will be obtained over a range of signal levels for both the Wide Field Channel {WFC}, and the High Resolution Channel {HRC}. ACS/WFC 10374 ACS photometric Stability This program consists of three parts. In the first part we will observe a subset of the ACS white dwarfs with HRC and ACS to verify repeatability to ~0.2%, because the filter shifts are based on photometric differences between stars of ~1%. These observations are also required to establish relative magnitudes of the primary WD standards at the 0.1% level. Targets should be GD153 and G191B2B, which seems to have the largest V mag error of ~0.008 mag. One orbit on the most important filters, including the grism and the prisms, should be expended with each camera for both stars for a total of 4 orbits. In the second part will observe with HRC and WFC a solar analog star, P330E, to estimate any shifts in the short and the long wavelength cutoffs of selected filters. Complete filter bandpasses can be derived directly from the ratio of grism observations with and without the filter in place. The grism is on filter wheel 1, while four filters of interest F330W, F344N, F660N, and F814W are on wheel 2. Each grism observation requires 3 settings: filter alone, filter+grism, and grism alone. In the third part we obtain high S/N photometric and spectroscopic observations of three red stars, VB-8 {M7}, 2M0038+18 {L3.5} and 2M0559-14 {T5} with HRC and WFC to verify the photometry at the new standard position and to obtain accurate calibration {1% or better} of the grism spectra. ACS/WFC 10412 The host galaxies of dust-reddened quasars We have used the 2MASS near-infrared and FIRST radio surveys, together with the Palomar Observatory Sky Survey plates to select a sample of dust-reddened, radio- intermediate quasars. We wish to use ACS to study the host galaxies of these quasars. The dust reddening of the quasars makes it possible to study the hosts at rest-frame optical-UV wavelengths much more easily than the hosts of normal quasars of similar bolometric luminosity. Our study will compare the hosts of our dust-reddened quasars to those of normal quasars from the HST archive to test the hypothesis that dust-reddened quasars are young objects, whose hosts still show morphological evidence of recent merger events which triggered the quasar. ACS/WFC/WFPC2 10402 The Formation and Evolution of Spirals: An ACS and WFPC2 Imaging Survey of Nearby Galaxies Over 50% of galaxies in the local universe are spirals. Yet the star formation histories and evolution of this crucial population remain poorly understood. We propose to combine archival data with new ACS/WFC and WFPC2 observations of 11 galaxies, to tackle a comprehensive investigation of nearby spirals covering the entire spiral sequence. The new observations will fill a serious deficiency in HST's legacy, and maximize the scientific return of existing HST data. The filter combination of UBVI, and Halpha is ideal for studying stellar populations, dust properties, and the ISM. Our immediate scientific objectives a {i} to use the resolved cluster populations, both young massive clusters and ancient globular clusters as a chronometer, to understand how spirals assembled as a function of time; {ii} study the rapid disruption properties of young clusters; and {iii} understand dust distributions in spirals from pc to kpc scales. Each of these goals provides an important step towards charting the evolution of galaxies, and an essential baseline for interpreting the galaxy populations being surveyed in both the early and present universe. The resolution of our survey, which exploits the excellent imaging capabilities of HST's two optical cameras, will enable us to understand the record of star cluster, and galaxy formation in a level of detail which is not possible for more distant systems. Finally, the proposed observations will provide a key to interpret an extensive, multiwavelength archive of space- and ground- based data at lower spatial resolution {SPITZER, CHANDRA, GALEX, NICMOS P alpha and H band imaging} for local spirals. FGS 10106 An Astrometric Calibration of the Cepheid Period-Luminosity Relation We propose to measure the parallaxes of 10 Galactic Cepheid variables. When these parallaxes {with 1-sigma precisions of 10% or better} are added to our recent HST FGS parallax determination of delta Cep {Benedict et al 2002}, we anticipate determining the Period-Luminosity relation zero point with a 0.03 mag precision. In addition to permitting the test of assumptions that enter into other Cepheid distance determination techniques, this calibration will reintroduce Galactic Cepheids as a fundamental step in the extragalactic distance scale ladder. A Period-Luminosity relation derived from solar metallicity Cepheids can be applied directly to extragalactic solar metallicity Cepheids, removing the need to bridge with the Large Magellanic Cloud and its associated metallicity complications. FGS 10386 Long Term Monitoring of FGS1r in Position Mode It is known from our experience with FGS3, and later with FGS1r, that an FGS on orbit experiences long term evolution, presumably due to disorption of water from the instrument's graphite epoxy composites. This manifests principally as a change in the plate scale and secondarily as a change in the geometric distortions. These effects are well modeled by adjustments to the rhoA and kA parameters which are used to transform the star selector servo angles into FGS {x, y} detector space coordinates. By observing the relative positions of selected stars in a standard cluster at a fixed telescope pointing and orientation, the evolution of rhoA and kA can be monitored and calibrated to preserve the astrometric performance of FGS1r. WFPC2 9964 Dynamical Masses of White Dwarfs from Resolved Sirius-Like Binaries In Cycle 8 we initiated a WFPC2 snapshot survey for resolved, ``Sirius-like'' systems containing hot white-dwarf companions of cooler main-sequence stars. Out of 17 systems observed to date, 8 have been resolved with WFPC2 by using UV filters. Two of the resolved systems---56 Persei and Zeta Cygni---have predicted or known orbital periods short enough that dynamical masses can be determined for the white dwarfs within reasonable times. These would thus add to the extremely small number of white dwarfs presently having accurately and directly measured masses. We propose to image them annually in the UV with WFPC2. In addition, we will observe Zeta Cyg with FGS in order to measure the absolute motion of the optical component, needed for the mass solution. We also propose to observe Sirius itself with WFPC2 over the next 3 Cycles. The resulting astrometric data will not only greatly improve the precision of the binary orbit and the dynamical mass measurements for both the main-sequence and white-dwarf components, but will also test definitively for the claimed presence of a third body in this famous system. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTAR 9783: Gsacq(2,3,3) results in Fine Lock Backup @ 111/0217z. At 111/02:16:50 GSacq(2,3,3) scheduled at 111/02:13:41 resulted in fine lock backup (2,0,2) due to scan step limit exceeded on FGS 3. Observations affected: NIC 30-31, ACS 114-117. Under investigation. COMPLETED OPS REQs: 17421-0 Genslew for proposal 10263 - slot 13 @ 110/1657z 17422-0 Genslew for proposal 10263 - slot 12 @ 110/1659z 17422-0 Genslew for proposal 10330 - slot 01 @ 110/1700z 17423-0 Genslew for proposal 10330 - slot 02 @ 110/1702z OPS NOTES EXECUTED: None SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 08 08 FGS Reacq 07 07 FHST Update 16 16 LOSS of LOCK SIGNIFICANT EVENTS: None |
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