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Daily 3777
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3777 PERIOD COVERED: DOYs 14-17 OBSERVATIONS SCHEDULED ACS/WFC/NIC2/WFPC2 9873 Main Sequence Turnoff Ages For Second Parameter Clusters in M33 In cycle 5, we were granted 40 orbits to study the early formation history of M33 by investigating the nature of the "second parameter" phenomenon among its globular star clusters. Discovered among the globular clusters of the Milky Way more than 30 years ago, the "second parameter" effect describes the degeneracy in the behavior of horizontal branch {HB} morphology with metal abundance. This degeneracy implies the existence of a second parameter, which, in addition to metal abundance, influences the morphology of the HB. We constructed {V, V-I} color-magnitude diagrams for 10 M33 halo globular clusters. From these diagrams, we measured the cluster metallicities and HB morphologies. Surprisingly, 8 of the 10 clusters display extremely red horizontal branches, with most of the HB stars lying near or on top of the red giant branch, yet their metal abundances are in the range -1.6 = [Fe/H] = -1.0. A likely explanation is that the halo clusters in M33 are several Gyr younger than those in the Milky Way. To test this hypothesis, we propose to obtain main sequence turnoff photometry for two of our M33 clusters with similar metallicities but vastly differing HBs - a so-called `second parameter pair.' This will help to answer the question of whether age is the second parameter among the M33 halo clusters and provide an important clue to the overall nature of the second parameter effect. NICMOS 8790 NICMOS Post-SAA calibration - CR Persistence Part 1. 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. ACS/WFC 10452 HST/ACS Mosaic of M51 A six-pointing ACS WFC mosaic of the galaxy pair M51 will be obtained in four filters, B, V, I and H-alpha. Four orbits per pointing will allow high-quality S/N images of the entire galaxy. 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 10429 Streaming Towards Shapley: The Mass of the Richest Galaxy Concentration in the Local Universe The 600 km/s motion of the Local Group {LG} with respect to the cosmic microwave background {CMB} is now known to high accuracy. However, its precise origin remains poorly understood. The contribution to the motion from the pull of the rich Shapley supercluster at z = 0.048 is particularly controversial. This extreme mass concentration contains more than 20 Abell clusters within 35 Mpc of its very rich central cluster A3558, and is recognized as both the optically richest and the most X-ray luminous structure in the local {z 0.1} universe. Yet, published values for the mass of Shapley continue to differ by an order of magnitude, and recent estimates of its pull on the LG range from negligible {20 km/s} to highly significant {300 km/s or more}. Here we propose to resolve this key issue by using ACS to measure high-precision surface brightness fluctuation {SBF} distances in order to make a direct measurement of the infall towards Shapley. We will target three Shapley foreground clusters where the infall is expected to be high {possibly 1000 km/s or more}, as well as the Shapley core, in order to test the assumption that it is at rest in the CMB. Prior to ACS, the Shapley region was unreachable for SBF, but ACS doubles the distance range of the SBF method with HST, enabling the distances to be measured to the required accuracy. The proposed measurements will place a firm limit on the largest mass fluctuation in the nearby universe and finally determine its contribution to the observed CMB dipole. ACS/HRC/WFC 10425 ACS Coronagraphic Imaging of Herbig Ae/Be Stars We can indirectly learn about the planet formation process by studying proto-planetary dust disks. In this proposed observational program, we focus on Herbig Ae/Be stars which are pre-main sequence intermediate mass stars {2-10 solar masses} thought to be immediate precursors to the Vega-excess stars like Beta Pictoris. We propose to take ACS coronagraphic images in the F606W filter of 6 Herbig Ae/Be stars, all of which have well constrained spectral energy distributions and are nearby {200pc}, suggesting possible disk sizes of 3" or larger in radius. We use the recent ACS coronagraph image of Herbig Ae/Be star, HD 141569, which shows a spectacular circumstellar disk, as a template for observing strategy and exposure time estimates. Our observing program involves contemporaneous comparison stars that will be used to subtract the point spread function. These images will constrain the size and possibly, the morphology of the circumstellar dust that may have disk, envelope or disk+envelope geometries. We will analyze these images quantitatively using 2-Dust, an axisymmetric radiative transfer dust code, to derive basic physical parameters of the dusty circumstellar matter such as mass, size, geometry, inclination angle and grain properties. ACS/WFC 10421 Searching for Ancient Mergers in Early Type Host Galaxies of Classical QSOs Recent HST imaging of QSO host galaxies indicates that at least a large fraction of QSOs reside in seemingly undisturbed elliptical hosts. However, our deep Keck spectroscopy of a sample of these host galaxies indicates that many of these objects were involved in a major starburst episode between 0.6 and 1.6 Gyr ago. We propose to obtain very deep ACS WFC observations of the five hosts in this sample that have the most reliable age determinations to search for fine structure indicative of a past merger event and to test the hypothesis that the elliptical hosts are the products of relatively recent merger events rather than old galaxies which formed at high redshifts. By establishing a firm connection between ancient mergers and the aging starbursts in these classical QSOs, we will be able to estimate the fraction of the total QSO population that results directly from mergers accompanied by massive starbursts and to place constraints on the duty cycle for QSO activity. ACS/HRC/WFC 10409 Highly episodic mass loss on the AGB: imaging in scattered stellar light We have discovered that some nearby bright carbon stars have detached circumstellar shells, emitting in CO mm lines as well as in visual stellar light scattered by dust and atoms {the resonance lines of NaI and KI}. The optical light is up to 35% linearly polarized. The shells are remarkably spherical, but both the CO data and the optical pictures show pronounced inhomogeneities on smaller {marginally resolved} scales. The latter fact introduces considerable uncertainties in mass-loss-rate estimates. We ascribe the existence of the shells to the He-shell flashes, and the inhomogeneities to hydrodynamic instabilities. However, the different observables {CO, atoms, dust} indicate significantly different structural patterns. In order to understand the different components of the shells, their interaction and origin, it is necessary to improve the imaging of the shells. In view of their faintness, relative to the stellar light scattered in the Earth's atmosphere, this can only be accomplished by using the HST. Maps of the distribution of the dust at high spatial resolution will efficiently constrain theoretical work on the origin of the shells and their evolution, and the inhomogeneities in them. We may be able to separate the dust and atomic scattered light components. Mass loss from carbon stars and other AGB stars contribute significantly to the abundances of many chemical elements {C, N, s-elements} and is not well understood. The present study may lead to important improvements in the study of mass-loss rates and mechanisms, and thus for nucleosynthesis in general. NIC3/WFPC2 10403 Ultraviolet Imaging of the UDF The Hubble Deep Field North has uninterrupted observations at wavelengths from Far-UV through NICMOS H-band, but the UDF goes no bluer than B-band. We propose to complete the UDF coverage with deep ultraviolet imaging of the Ultra-Deep Field {UDF} with the ACS-SBC in the Far-UV {1500 Angstrom} and WFPC2 in the Near-UV {F300W}. We will reach point source limits of ABmag=28.5, a factor of ten fainter than the GALEX ultradeep surveys. Our dataset will add to the value of the UDF legacy, and requires the unique capabilities of HST. In the spirit of the UDF, we submit this proposal in the Treasury category. We request a modest allocation of observing time for a Treasury program: 62 orbits. We will provide science quality images and photometric catalogs to enable a range of research topics by the community. The science goals of the team are to investigate the episode of strong star formation activity in galaxies out to z=1, through the rest-frame FUV luminosity function and the internal color structure of galaxies. Far-UV number counts suggest that moderate redshift {z~0.5} starbursts are undergoing a single, rapid burst of star-formation. We will investigate this result by measuring the faint-end slope, alpha, of the luminosity function. We will measure the star formation properties of moderate redshift starburst galaxies and compare their morphologies in the UV, optical, and near-IR. This catalog of starbursts will also be important to the astronomical community in correlating unobscured star-formation with the sources detected in the Spitzer Space Telescope legacy observations of the field. With the high spatial resolution data, will set strict limits on the flux escaping in intermediate redshift {1z2} galaxies at wavelengths below the rest-frame Lyman limit, and thus infer the contribution of star forming galaxies at z~5 to the metagalactic ionizing radiation. ACS/HRC/WFC/WFPC 10384 2 Focus Monitor The focus of HST is measured from WFPC2/PC and ACS/HRC images of stars. Multiple exposures are taken in parallel over an orbit to determine the influence of breathing on the derived mean focus. Observations are taken of clusters with suitable orientations to ensure stars appear in all fields. NIC1/NIC2/NIC3 10380 Cycle 13 NICMOS dark current, shading profile, and read noise monitoring program The purpose of this proposal is to monitor the dark current, read noise, and shading profile for all three NICMOS detectors throughout the duration of Cycle 13. This proposal is an essentially unchanged continuation of PID 9993 which cover the duration of Cycle 12. 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. WFPC2 10359 WFPC2 CYCLE 13 Standard Darks This dark calibration program obtains dark frames every week in order to provide data for the ongoing calibration of the CCD dark current rate, and to monitor and characterize the evolution of hot pixels. Over an extended period these data will also provide a monitor of radiation damage to the CCDs. WFPC2 10357 Saturn's Inner Satellites at True Opposition We request one HST orbit to observe Janus, Epimetheus, Mimas, and Enceladus with WFPC2 exactly at opposition, when the Earth transits the center of the solar disk seen from Saturn on UT 13/14 January 2005. Data obtained at this unique viewing geometry are essential to determining physical properties of the moon's surface, related to its emplacement and evolution, and critical for the interpretation of photometric data obtained by Cassini at higher phase angles. This single observation will be the capstone of 9 years of legacy HST WFPC2 observations of the Saturnian system {Cycles 6-12, R. French, PI} from which we have constructed precise, multiwavelength phase curves which demonstrate how the reflectance of these satellites varies with solar phase angle from 0.07 to 6.4 degrees. Each satellite exhibits a dramatic increase in brightness, or "opposition effect", as phase angles decrease below 1 degree. Since 1998 {Cycle 7} the minimum observable phase angle at opposition has decreased each year to 0.07 degrees in Cycle 12; however, the absolute minimum observable phase angle, about 0.02 degrees {limited by the angular size of the Sun viewed from Saturn}, has not been accessible until Cycle 13. Using the same set of broadband filters for continuity with our previous programs, we will place observations made during the Earth transit on the existing UVBRI phase curves and establish the amplitude of each satellite's opposition surge. From these observations we will determine surface properties such as porosity, grain size distribution and particle opacity using radiative transfer models. While the Cassini spacecraft will obtain images at larger phase angles, it will miss entirely the narrow brightness surge near opposition due to orbital constraints. Because these inner satellites will be either lost in or contaminated by the glare of the fully open rings, they are not accessible to ground-based telescopes. The 2005 opposition presents the only opportunity for HST to observe the Saturnian system during this rare planetary alignment. The next transit of Earth across the solar disk seen from Saturn occurs in 2020; the next central transit occurs in 2049. 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. NIC/NIC3 10226 The NICMOS Grism Parallel Survey 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 10217 The ACS Fornax Cluster Survey The two rich clusters nearest to the Milky Way, and the only large collections of early- type galaxies within ~ 25 Mpc, are the Virgo and Fornax Clusters. We propose to exploit the exceptional imaging capabilities of the ACS/WFC to carry out the most comprehensive imaging survey to date of early-type galaxies in Fornax: the ACS Fornax Cluster Survey. Deep ACS/WFC images -- in the F475W {g'} and F850LP {z'} bands -- will be acquired for 44 E, S0, dE, dE, N and dS0 cluster members. In Cycle 11, we initiated a similar program targeting early-type galaxies in the Virgo Cluster {the ACS Virgo Cluster Survey; GO-9401}. Our proposed survey of Fornax would yield an extraordinary dataset which would complement that already in hand for Virgo, and allow a definitive study of the role played by environment in the structure, formation and evolution of early-type galaxies and their globular cluster systems, nuclei, stellar populations, dust content, nuclear morphologies and merger histories. It would also be a community resource for years to come and, together with the ACS Virgo Cluster Survey, constitute one of the lasting legacies of HST. 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/NIC1/WFC 10190 The Star Formation History and Metallicity Evolution of M33: A Comprehensive Study of Disk Evolution We will obtain deep, panchromatic imaging photometry of stellar populations in four fields ranging from 0.5 to 4 scale lengths across the disk of the Local Group spiral M33. The observations are designed to detect the oldest main-sequence turnoffs in three outer disk fields, and to reach the crowding limit in the innermost field. We will combine the photometry data with information we already have in-hand on abundances from stars and H II regions in M33 to derive the star formation history and metallicity evolution of the M33 disk. The information from our four fields will allow us to obtain {1} the ages of the oldest disk stars and the radial variation of their ages; {2} the radial variation of the star formation history and its nature {e.g., constant, declining, or bursting}; and {3} the metallicity distribution in each field and the time evolution of the metallicity gradient. Our team, an experienced mix of photometrists, spectroscopists, and galaxy evolution theorists, will use the results from this program to construct a comprehensive chemo- dynamical model for the M33 disk. This detailed study of M33 will be a key in developing an understanding of the formation and evolution of disks that can be applied to studies of disks at both low and high redshift, and will also yield a wealth of information on stellar populations, chemical evolution, and star clusters that will be of great value to future investigators. NIC2 10176 Coronagraphic Survey for Giant Planets Around Nearby Young Stars A systematic imaging search for extra-solar Jovian planets is now possible thanks to recent progress in identifying "young stars near Earth". For most of the proposed young {~ 30 Myrs} and nearby {~ 60 pc} targets, we can detect a few Jupiter-mass planets as close as a few tens of AUs from the primary stars. This represents the first time that potential analogs of our solar system - that is planetary systems with giant planets having semi-major axes comparable to those of the four giant planets of the Solar System - come within the grasp of existing instrumentation. Our proposed targets have not been observed for planets with the Hubble Space Telescope previously. Considering the very successful earlier NICMOS observations of low mass brown dwarfs and planetary disks among members of the TW Hydrae Association, a fair fraction of our targets should also turn out to posses low mass brown dwarfs, giant planets, or dusty planetary disks because our targets are similar to {or even better than} the TW Hydrae stars in terms of youth and proximity to Earth. Should HST time be awarded and planetary mass candidates be found, proper motion follow-up of candidate planets will be done with ground-based AOs. ACS/WFC/NIC3 10127 Imaging a protocluster at z=3.1: Effects of environment and evolution on galaxy populations in the early universe We propose imaging a rich protocluster, 0316-26 at z = 3.13, with 31 confirmed Lya cluster members. The bright radio galaxy host is identified with the progenitor of the dominant cluster galaxy. Because its redshift places Lya into an ACS narrow-band filter, the protocluster provides a unique laboratory for studying galaxies at a crucial epoch in the evolution of the Universe. We shall {i} measure and compare sizes, morphologies and colors of galaxies from populations detected using 4 different selection techniques {Lyman and 4000A breaks, Lya and [OIII] excesses}, {ii} study effects of an overdense environment by comparing the properties of protocluster galaxies with z~3 field galaxies from GOODS, {iii} study effects of evolution by relating our data to observations of similar protocluster/cluster targets at redshifts z = 4.1, 2.2, and 1.2, and {iv} constrain the formation of the most massive cluster galaxies by investigating the spatial distribution, Lya equivalent widths and other properties within the 5" radio galaxy host. The ultimate aim is to disentangle the history of structure development and stellar evolution for rich clusters of galaxies. WFPC2 10112 HST Observations of Astrophysically Important Visual Binaries This is a continuation of a project begun in Cycle 7 and continued up through Cycle 11. The program consists of annual or biannual WFPC2 or FGS observations of three visual binary stars that will ultimately yield fundamental astrophysical results, once their orbits and masses are determined. Our targets are the following: {1} Procyon {P = 41 yr}, for which our first WFPC2 images yielded an extremely accurate angular separation of the bright F star and its much fainter white-dwarf companion. Combined with ground-based astrometry of the bright star, our observation significantly revised downward the derived masses, and brought Procyon A into excellent agreement with theoretical evolutionary tracks for the first time. With the continued monitoring proposed here, we will obtain masses to an accuracy of better than 1%, providing a testbed for theories of both Sun- like stars and white dwarfs. {2} G 107-70, a close double white dwarf {P = 19 yr} that promises to add two accurate masses to the tiny handful of white-dwarf masses that are directly known from dynamical measurements. {3} Mu Cas {P = 21 yr}, a famous metal- deficient G dwarf for which accurate masses will lead to the stars' helium contents, with cosmological implications. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTAR 9665: GS Acquisition (1,3,3)required two attempts to enter FL with SRLE @ 08:09:06Z. Under investigation. COMPLETED OPS REQs: None OPS NOTES EXECUTED: 0900-1 COMMAND PROBLEM @ 017/0502z 0916-0 Tabulation of Slew Attitude Error (Miss-distance) @ 017/0056z 0900-1 COMMAND PROBLEM @ 017/0502z 0916-0 Tabulation of Slew Attitude Error (Miss-distance) @ 017/0056z SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 33 33 FGS Reacq 26 26 FHST Update 54 54 LOSS of LOCK SIGNIFICANT EVENTS: None |
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