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Daily Report #3749
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3749 PERIOD COVERED: DOYs 338-340 OBSERVATIONS SCHEDULED NIC3 9846 The Origins of Sub-stellar Masses: Searching for the End of the IMF Is there a preferred scale that defines the end of the IMF? We propose to test this hypothesis by conducting a deep spectroscopic survey of extremely low mass objects in the embedded young cluster associated with NGC1333. At a distance of only 300pc, this cluster is one of the nearest examples of a dense young cluster. We will be able to obtain R=200 spectra and photometry for 40-60 cluster members with masses between 5-40 Jupiter masses at an age of 1 Myr observed through A{v}10 mag. This will enable us to estimate temperatures and luminosities for all sources detected in the survey. We will compare their positions in an H-R diagram to PMS evolutionary tracks in order to estimate their ages and masses. For a solar metallicity cloud at a temperature of 10 K, the minimum mass for fragmentation is thought to be 10 Jupiter masses. A statistically significant sample of objects detected below this limit would challenge the role of hierarchical fragmentation in limiting substellar masses. The proximity of this cluster combined with the unique sensitivity, wavelength coverage, and multi-object spectroscopic capability of NICMOS on HST make this experiment possible. ACS/HRC 9792 Uncovering the CV population in M15: a deep, time-resolved, far-UV survey of the We propose to carry out a deep, far-ultraviolet {FUV}, time-resolved for faint cataclysmic variables {CVs} and other dynamically-formed objects in the globular cluster {GC} M15. We will use the ACS/SBC to carry out 6 epochs of FUV imaging of this cluster in a single filter, and will use two additional visits to obtain images in other FUV and NUV filters. Since crowding is not a problem in the FUV, this will yield time-resolved FUV photometry of all blue objects in the cluster core. Our CV census will be both deep enough to be essentially complete and ``broad'' enough to involve all of the following CV characteristics: {1} UV brightness; {2} blue FUV spectral shape; {3} strong CIV and HeII emission; {4} short time-scale {$sim$ minutes} variability {flickering, WD spin}; {6} intermediate time-scale {$sim$ hours} variability {orbital variations}; {7} long time-scale {$sim$ weeks} variability {dwarf nova eruptions}. We will thus find the CV population in M15, if it exists. In addition, our survey will detect numerous blue stragglers and hot white dwarfs, as well as any other blue objects near the core. Finally, our photometry will yield high-quality FUV light curves of the two low-mass x-ray binaries in M15. ACS/WFC 9779 Giant Lya Halos Around High Redshift Radio Galaxies We propose to use the ACS + ramp filter to image the morphologies of several high redshift, giant Lya emission line halos associated with radio galaxies. High redshift radio galaxies are the likely precursors of the most massive elliptical galaxies known today. There is increasing evidence that they are forming in the centers of giant halos in overdense galaxy regions or `protoclusters'. The halos provide a unique diagnostic to study the formation of these massive galaxies and determine the importance of AGN/starburst feedback during this process. The capability of HST to resolve fine detail is essential for the interpretation of their complex morphologies. Our targets have also a number of Lya excess galaxies near the halos which fall within the field-of-view of the ACS + ramp filters. Our images will resolve these systems and we will investigate whether there is morphological evidence for starburst outflows. Starburst winds have been proposed as a source of heat and chemical enrichment for protoclusters, which may significantly affect their evolution. ACS/WFC 9722 Life in the fast lane: The dark-matter distribution in the most massive galaxy clusters in the Universe at z0.5 We propose two-filter ACS observations of a complete sample of 12 very X-ray luminous galaxy clusters at 0.5z0.7 as a cornerstone of a comprehensive multi- wavelength study of the properties of the most massive clusters in the universe. Our sample includes the famous systems Cl0016+16 and MS0451-03; all other clusters are new discoveries from the MACS survey. Being the counterparts of the best-studied systems at lower and higher redshift and comprising ALL massive clusters at 0.5z0.7 observable from Mauna Kea this sample will become the ultimate reference for cluster studies at z0.5. HST's unique capabilities will allow us to: 1} measure accurately the clusters' dark matter distribution on scales from tens to more than 500/h_50 kpc from observations of strong and weak gravitational lensing, 2} use galaxy-galaxy lensing to measure the shape, extent, and mass content of the dark-matter halos of both cluster and field galaxies, and 3} study the color morphology of mergers and the star formation history of galaxies in a high-density environment. The proposed observations are complemented by Chandra observations of all our targets {all 12 awarded, 11 executed to date} which provide independent constraints on the dark matter and gas distribution in the cluster cores, as well a by extensive groundbased observations of weak lensing on yet larger scales, galaxy dynamics, and the SZ effect. NIC1/NIC2/NIC3 8794 NICMOS Post-SAA calibration - CR Persistence Part 5 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. ACS/WFC/NIC2/WFPC 10413 2 Resolving the Red Giant Population in Early Type Galaxies This project addresses the fundamental issue of the age and abundance of the stellar populations in early type galaxies. We propose deep imaging observations with ACS/WFC in F606W, F814W, and NICMOS/NIC2 in F110W, F160W to create optical/IR color-magnitude diagrams of the upper red giant branch in the nearest example of a bona fide elliptical galaxy, NGC3379, and simultaneously in the disk and halo of its companion, the S0 galaxy NGC3384. These observations will build upon the results from our NICMOS study of NGC3379, which produced the first deep IR color-magnitude data for a normal, luminous elliptical galaxy. This is the most direct way to establish the metallicity, metallicity spread, and presence of intermediate age populations in these representative Hubble types, exploring their star formation histories and evolution. The data will enable comparison with M32, the M31 halo, NGC5128, and other nearby galaxies similarly observed with HST. ACS/HRC 10377 ACS Earth Flats High signal sky flats will be obtained by observing the bright Earth with the HRC and WFC. These observations will be used to verify the accuracy of the flats currently used by the pipeline and will provide a comparison with flats derived via other techniques: L- flats from stellar observations, sky flats from stacked GO observations, and internal flats using the calibration lamps. Weekly coronagraphic monitoring is required to assess the changing position of the spots. 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. 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 10326 The Morphological, Photometric, and Spectroscopic Properties of Intermediate Redshift Cluster Galaxies We will use the ACS/WFC to image 8 fields in the outskirts of the kT=5.8keV, X-ray cluster RX J0152-13 at z=0.83, for which we obtained imaging in four central fields during Cycle 11. The resulting wide-field mosaic of RX J0152-13 will enable direct study of the population of galaxies falling into this cluster and will provide a much needed comparison to our on-going wide-field study of the more massive, 10.5keV cluster MS1054-03 at the same redshift. Imaging RX J0152-13 to twice its viral radius enables us to: {1} trace the transformation of infalling field spirals into cluster early-types using, e.g., the morphology-density relation to large radii and very low local densities; {2} determine the importance of galaxy-galaxy interactions, i.e., whether the frequency of such encounters in the infall region is as unexpectedly high as found in MS1054-03; and {3} study in detail the star-formation histories of the most recently accreted members via accurate colors and morphologies. A comparison of RX J0152-13 with MS1054-03 will also allow us to directly probe the dependence of galaxy evolution on cluster mass. Only by pairing the wide-field ACS mosaic of RX J0152-13 with multi-object spectroscopy from the Magellan, Keck, and VLT telescopes can we test predictions from galaxy formation models, understand how field spirals evolve into early-type cluster members, and better constrain the formation of galaxies in general. ACS/WFC 10286 Probing the Dynamics and Shock Physics of the Cas A Supernova Remnant Cassiopeia A {Cas A; SN 1680} is the youngest known and closest example of an oxygen-rich, core-collapse supernova remnant. A two-year WFPC2 survey of part of the remnant yielded many new insights including realization of the stunning amount of fine- scale detail present in the ejecta, and the first precise location of the reverse shock front in the main shell via rapid emission and structural changes visible over 2 yrs. In addition, these data revealed over 100 new ejecta knots located out ahead of the forward blast wave in a small region where only a handful were known from ground-based images. We propose a follow-up survey program aimed at obtaining hi-res images of the entire remnant in the ejecta's four major emission lines. A separate set of ACS and NIC3 [Si VI] images of the NW reverse shock filaments will be taken 3-4 months following the main Cycle 12 survey images. These will allow us to the trace individual ejecta knot deceleration dynamics, excitation, and evolution during reverse shock passage. Analysis of the emission line fluxes will make use of custom shock models generated by us for Cas A. These data will also provide data on outer knot chemistry and expansion asymmetries particularly in regard to the collimation of the NE and SW jets of O, Si, Ca- rich ejecta. A major aim of this program is to acquire a superb two-year image database covering the entire remnant to allow a detailed shock physics and dynamics study. 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. 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 10169 Star Formation in Luminous Infrared Galaxies: giant HII Regions and Super Star Clusters Luminous Infrared Galaxies {LIRGs, LIR = 10^11-10^12Lsol} and Ultraluminous Infrared Galaxies {LIR10^12Lsol} account for approximately 75% of all the galaxies detected in the mid-infrared in the redshift range z=0-1.5. In the local universe it is found that LIRGs are predominantly powered by intense star formation {SF}. However, the physical conditions and processes governing such dramatic activity over scales of tens to a few hundred parsecs are poorly known. In the last decade HST has been playing a significant role, mainly with the discovery of super star clusters {SSCs}, and more recently, giant HII regions. Based on observations of a few LIRGs, we found that these giant HII regions and associated SSCs appear to be more common in LIRGs than in normal galaxies, and may dominate the star formation activity in LIRGs. A larger sample is required to address fundamental questions. We propose an HST/NICMOS targeted campaign of a volume limited sample {v5200km/s} of 24 LIRGs. This proposal will probe the role of giant HII regions in the overall energetics of the current star formation, their relation to SSCs, and the dependence of star formation properties on other parameters of LIRGs. Such detailed knowledge of the SF properties of LIRGs in the local universe is essential for understanding galaxies at high redshift. NIC2 10160 The nuclear scattering geometry of Seyfert galaxies Orientation-based unification schemes are now well-established as the basis for understanding the relationships between different classes of AGN. However, our recent study of the optical polarization properties of Seyfert 1 galaxies indicates that scattered light emerging from these objects often follows a different path to that in Seyfert 2's, indicating that the simplest unification geometry is incomplete. We have developed a generic scattering model for Seyfert nuclei which includes a compact, equatorial scattering region located within the circum-nuclear torus and the 'classic' polar scattering region outside it. We propose to test this model by using NICMOS to make NIR imaging observations that will allow us to isolate the two scattering regions within individual objects. ACS/HRC 10137 Cluster Archeology: The Origin of Ultra-compact Dwarf Galaxies Ultra-compact dwarf {UCD} galaxies are a new type of galaxy we have discovered in the central regions of the Fornax and Virgo galaxy clusters. Our most recent observations in the Fornax Cluster show that UCDs outnumber normal galaxies in the centre of that cluster. Here we propose snapshot imaging of UCDs in the Fornax and Virgo clusters to test theories of how these fascinating objects formed. In particular we wish to image Virgo cluster UCDs for which we have ground-based Keck spectroscopy to test predictions that they formed more recently than the Fornax UCDs. 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. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) None COMPLETED OPS REQs:None OPS NOTES EXECUTED:None SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 18 18 FGS Reacq 24 24 FHST Update 33 33 LOSS of LOCK SIGNIFICANT EVENTS: None |
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