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Daily 3825
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT # 3825 PERIOD COVERED: DOYs 84-86 OBSERVATIONS SCHEDULED 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. ACS/WFC/WFPC2 10424 The White Dwarf Cooling Age and Dynamical History of the Metal-Poor Globular Cluster NGC 6397 We propose to determine the white dwarf cooling age in the nearest metal-poor {[Fe/H]=- 2} globular cluster, NGC 6397. This globular cluster provides the best opportunity to test the white dwarf cooling age in such a metal-poor system and at the same time provide a comparison with the more metal-rich cluster {M4} which we recently successfully observed with HST. Any {or even no} age difference between these clusters will be important in understanding the age-metallicity relation for these systems which reflects the star formation history in the early Galaxy. The absolute age is an important cosmological constraint. We expect to be able to detect age DIFFERENCES between these clusters at the 0.5 Gyr level and absolute ages should be accurate to 1.0 Gyr. In addition, and in contrast with M4, NGC 6397 is highly dynamically evolved, has a collapsed core, and the distribution of its white dwarfs throughout the cluster have almost certainly been modified by dynamical processes. We are using N-body simulations specifically developed for this cluster to understand these modifications and to include their effects in our measurement of the white dwarf luminosity function and cooling age. Among the dynamical questions we expect to answer with this proposal a 1} what was the primordial binary frequency in NGC 6397? 2} can we explain the high central concentration with a population of massive white dwarfs and/or neutron stars? 3} do we see sufficient central binaries to reverse the core collapse of the cluster? ACS/WFC 10378 ACS Polarimetry Calibration Observations are made of the Boomerang Nebula {highly polarized reflection nebula} to calibrate the ACS polarizers. ACS/HRC/WFC 10370 CCD Hot Pixel Annealing Hot pixel annealing will continue to 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 the annealing, a bias and four dark images will be taken before and after the annealing procedure for both WFC and HRC. The HRC darks are taken in parallel with the WFC darks. The charge transfer efficiency {CTE} of the ACS CCD detectors declines as damage due to on-orbit radiation exposure accumulates. This degradation has been closely monitored at regular intervals, because it is likely to determine the useful lifetime of the CCDs. We will now combine the annealing activity with the charge transfer efficiency monitoring and also merge into the routine dark image collection. To this end, the CTE monitoring exposures have been moved into this proposal . 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/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/HRC 10255 A Never Before Explored Phase Space: Resolving Close White Dwarf / Red Dwarf We propose an ACS Snapshot imaging survey to resolve a well-defined sample of highly probable white dwarf plus red dwarf close binaries. These candidates were selected from a search for white dwarfs with infrared excess from the 2MASS database. They represent unresolved systems {separations less than approximately 2" in the 2MASS images} and are distributed over the whole sky. Our HST+ACS observations will be sensitive to a separation range {1-20 AU} never before probed by any means. The proposed study will be the first empirical test of binary star parameters in the post-AGB phase, and cannot be accomplished from the ground. By resolving as few as 20 of our ~100 targets with HST, we will be able to characterize the distribution of orbital semi- major axes and secondary star masses. ACS/WFC/NIC2 10189 PANS-Probing Acceleration Now with Supernovae Type Ia supernovae {SNe Ia} provide the most direct evidence for an accelerating Universe, a result widely attributed to dark energy. Using HST in Cycle 11 we extended the Hubble diagram with 6 of the 7 highest-redshift SNe Ia known, all at z1.25, providing conclusive evidence of an earlier epoch of cosmic deceleration. The full sample of 16 new SNe Ia match the cosmic concordance model and are inconsistent with a simple model of evolution or dust as alternatives to dark energy. Understanding dark energy may be the biggest current challenge to cosmology and particle physics. To understand the nature of dark energy, we seek to measure its two most fundamental properties: its evolution {i.e., dw/dz}, and its recent equation of state {i.e., w{z=0}}. SNe Ia at z1, beyond the reach of the ground but squarely within the reach of HST with ACS, are crucial to break the degeneracy in the measurements of these two basic aspects of dark energy. The SNe Ia we have discovered and measured with HST in Cycle 11, now double the precision of our knowledge of both properties. Here we propose to quadruple the sample of SNe Ia at z1 in the next two cycles, complementing on-going surveys from the ground at z1, and again doubling the precision of dark energy constraints. Should the current best fit model prove to be the correct one, the precision expected from the current proposal will suffice to rule out a cosmological constant at the 99% confidence level. Whatever the result, these objects will provide the basis with which to extend our empirical knowledge of this newly discovered and dominant component of the Universe, and will remain one of the most significant legacies of HST. In addition, our survey and follow-up data will greatly enhance the value of the archival data within the target Treasury fields for galaxy studies. NIC1/NIC2 10161 Fresh ammonia-ice on Jupiter: The northern equatorial region. The proposed multi-band imaging of one of the most dynamic regions on Jupiter will complement recent space-based infrared datasets and will provide crucial constraints to models of Jovian atmospheric dynamics. NICMOS is sensitive to the Jovian troposphere at and above the visible cloud decks. We selected six NICMOS filters with varying levels of atmospheric opacity to observe cloud features as they rotate from the central meridian to the limb, a strategy that will maximize the vertical resolution of our retrievals of cloud heights, haze opacity, and gaseous ammonia concentration. With these filters and the excellent NICMOS spatial resolution {nearly an order of magnitude improvement over Galileo NIMS images of the northern equatorial region}, we will determine the smaller-scale structure of fresh NH3 clouds and provide cloud heights as constraints for models of convection and dynamics associated with 5-micron hotspots. HST is essential for this project, since no other observatory can provide the necessary spatial resolution, and no ground-based or space-based telescopes can observe the ammonia bands we have selected. ACS/WFC 10152 A Snapshot Survey of a Complete Sample of X-ray Luminous Galaxy Clusters from Redshift 0.3 to 0.7 We propose a public, uniform imaging survey of a well-studied, complete, and homogeneous sample of X-ray clusters. The sample of 73 clusters spans the redshift range between 0.3-0.7. The samples spans almost 2 orders of magnitude of X-ray luminosity, where half of the sample has X-ray luminosities greater than 10^44 erg/s {0.5- 2.0 keV}. These snapshots will be used to obtain a fair census of the the morphology of cluster galaxies in the cores of clusters, to detect radial and tangential arc candidates, to detect optical jet candidates, and to provide an approximate estimate of the shear signal of the clusters themselves, and potentially an assessment of the contribution of large scale structure to lensing shear. ACS/HRC 10133 HST / Chandra Monitoring of a Dramatic Flare in the M87 Jet As the nearest galaxy with an optical jet, M87 affords an unparalleled opportunity to study extragalactic jet phenomena at the highest resolution. During 2002, HST and Chandra monitoring of the M87 jet detected a dramatic flare in knot HST-1 located ~1" from the nucleus. As of late 2003 its brightness has increased twenty-fold in the optical band, and continues to increase sharply; the X-rays show a similarly dramatic outburst. In both bands HST-1 now greatly exceeds the nucleus in brightness. To our knowledge this is the first incidence of an optical or X-ray outburst from a jet region which is spatially distinct from the core source; this presents an unprecedented opportunity to study the processes responsible for non-thermal variability and the X-ray emission. We propose seven epochs of monitoring during Cycle 13, as well as seven epochs of Chandra/ACIS observation {5ksec each}. We also include a brief HRC/ACS observations that will be used to gather spectral information and map the magnetic field structure. This monitoring is continued into Cycles 14 and 15. The results of this investigation are of key importance not only for understanding the nature of the X-ray emission of the M87 jet, but also for understanding flares in blazar jets, which are highly variable, but where we have never before been able to resolve the flaring region in the optical or X-rays. These observations will allow us to test synchrotron emission models for the X-ray outburst, constrain particle acceleration and loss timescales, and study the jet dynamics associated with this flaring component. Revisions 6 Oct 2004: We are replacing STIS visits 1-7 with ACS/HRC observations in new visits 31- 37. WFPC2 10132 UV Confirmation of New Quasar Sightlines Suitable for the Study of Intergalactic Helium The reionization of intergalactic helium is thought to have occurred between redshifts of about 3 and 4. The study of HeII Lyman-alpha absorption towards a half-dozen quasars at 2.7z3.5 demonstrates the great potential of such probes of the IGM, but the current critically-small sample limits confidence in resulting cosmological inferences. The requisite unobscured quasar sightlines to high-redshift are extremely rare, especially due to severe absorption in random intervening Lyman-limit systems, but SDSS provides hundreds of bright, new quasars at such redshifts potentially suitable for HeII studies. Our cycle 13 SNAP program proposes to verify the UV detectability of 40 new, bright, z2.9 SDSS quasars, but with special emphasis on extending helium studies to the highest redshift sightlines. Our proposed approach has already proven successful, and additional sightlines will enable follow-up spectral observations to measure the spectrum and evolution of the ionizing background radiation, the density of intergalactic baryons, and the epoch of reionization of the IGM. ACS/HRC 10094 Mid-Ultraviolet Spectral Templates for Old Stellar Systems We propose a three-year program to provide both observational and theoretical mid- ultraviolet {2300A -- 3100A} spectral templates for interpreting the age and metallicity of globular clusters and elliptical galaxies from spectra of their integrated light. The mid-UV is the region most directly influenced by stellar age, and is observed directly in optical and infrared studies of high-redshift quiescent systems. The reliability of age and metallicity determinations remains questionable until non-solar metallicities and abundance ratios are considered, and stars spanning the color-magnitude diagram are included, as we propose here. With archival HST STIS spectra we have improved the list of mid-UV atomic line parameters, then calculated spectra from first principles which match observed spectra of standard stars up to one- fourth solar metallicity. We will extend both observations and calculations to stars of solar metallicity and beyond, and to those in short-lived stages hotter than the main-sequence turnoff, stars not currently well-represented in empirical libraries. The necessary line-list improvements will come from new high-resolution mid-UV spectra of nine field stars. A key application of the results of this program will be to the old systems now being discovered as `Extremely Red Objects' at high redshifts. Reliable age-dating of these places constraints on the epoch when large structures first formed in the universe. 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.) HSTAR 9751: Full Maneuver Update (U1,2FM) failure @ 05/084/16:09:56z The first of two U1,2FM Full Maneuver Updates scheduled at 084/16:09:56 and 084/16:12:41 respectively, failed with error box results indicating "2FAILED". A single 486 ESB message 901 was observed at 084/16:10:49. Under investigation. HSTAR 9752: GSAcq(1,2,1) failed to RGA control @ 5/84/16:15:26 due to search radius limit exceeded on the primary FGS1. Per PCS/SE, the image of the secondary guide star location indicates no star at that location. Ref HSTAR# 9751, the second FM Update at 084/16:12:41 showed attitude error: V1=41.217, V2=-17.206, V3=-15.626 (arcsec). Subsequent GSAcq(3,0,3) at 084/17:40:29 was successful. Possible Observations affected:ACS 189, 190 WFPCII 128,129. Under investigation. COMPLETED OPS REQs: 17709-0 R/T Map @084/1651z OPS NOTES EXECUTED: None SCHEDULED SUCCESSFUL FAILURE TIMES FGS Gsacq 34 33 084/1615z (HSTAR#9752) FGS Reacq 17 17 FHST Update 42 41 084/1609z (HSTAR#9751) LOSS of LOCK SIGNIFICANT EVENTS: None |
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