Status Report

NASA Hubble Space Telescope Daily Report # 4610

By SpaceRef Editor
May 15, 2008
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NASA Hubble Space Telescope Daily Report # 4610


Continuing to collect World Class Science

PERIOD COVERED: 5am May 13 – 5am May 14, 2008 (DOY 134/0900z-135/0900z)


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=3Ddate/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 DARKs. 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.

NIC2/WFPC2 11142

Revealing the Physical Nature of Infrared Luminous Galaxies at 0.3We aim to determine physical properties of IR luminous galaxies at 0.3 0.8mJy and their mid-IR spectra have already provided the majority targets with spectroscopic redshifts {0.31 ULIRGs, as in the local Universe. {2} study the co-evolution of star formation and blackhole accretion by investigating the relations between the fraction of starburst/AGN measured from mid-IR spectra vs. HST morphologies, L{bol} and z. {3} obtain the current best estimates of the far-IR emission, thus L{bol} for this sample, and establish if the relative contribution of mid-to-far IR dust emission is correlated with morphology {resolved vs. unresolved}.

S/C 11163

Accreting Pulsating White Dwarfs in Cataclysmic Variables

Recent ground-based observations have increased the number of known pulsating white dwarfs in close binaries with active mass transfer {cataclysmic variables} from 5 to 11 systems. Our past Cycles 8 and 11 STIS observations of the first 2 known, followed by our Cycle 13 SBC observations of the next 3 discovered, revealed the clear presence of the white dwarf and increased amplitude of the pulsations in the UV compared to the optical. The temperatures derived from the UV spectra show 4 systems are much hotter than non-interacting pulsating white dwarfs. A larger sample is needed to sort out the nature of the instability strip in accreting pulsators i.e. whether effects of composition and rotation due to accretion result in a well- defined instability strip as a function of Teff.

WFPC2 10890

Morphologies of the Most Extreme High-Redshift Mid-IR-Luminous Galaxies

The formative phase of the most massive galaxies may be extremely luminous, characterized by intense star- and AGN-formation. Till now, few such galaxies have been unambiguously identified at high redshift, restricting us to the study of low-redshift ultraluminous infrared galaxies as possible analogs. We have recently discovered a sample of objects which may indeed represent this early phase in galaxy formation, and are undertaking an extensive multiwavelength study of this population. These objects are bright at mid-IR wavelengths {F[24um]>0.8mJy}, but deep ground based imaging suggests extremely faint {and in some cases extended} optical counterparts {R~24-27}. Deep K-band images show barely resolved galaxies. Mid-infrared spectroscopy with Spitzer/IRS reveals that they have redshifts z ~ 2-2.5, suggesting bolometric luminosities ~10^{13-14}Lsun! We propose to obtain deep ACS F814W and NIC2 F160W images of these sources and their environs in order to determine kpc-scale morphologies and surface photometry for these galaxies. The proposed observations will help us determine whether these extreme objects are merging systems, massive obscured starbursts {with obscuration on kpc scales!} or very reddened {locally obscured} AGN hosted by intrinsically low-luminosity galaxies.

WFPC2 11113

Binaries in the Kuiper Belt: Probes of Solar System Formation and Evolution

The discovery of binaries in the Kuiper Belt and related small body populations is powering a revolutionary step forward in the study of this remote region. Three quarters of the known binaries in the Kuiper Belt have been discovered with HST, most by our snapshot surveys. The statistics derived from this work are beginning to yield surprising and unexpected results. We have found a strong concentration of binaries among low-inclination Classicals, a possible size cutoff to binaries among the Centaurs, an apparent preference for nearly equal mass binaries, and a strong increase in the number of binaries at small separations. We propose to continue this successful program in Cycle 16; we expect to discover at least 13 new binary systems, targeted to subgroups where these discoveries can have the greatest impact.

WFPC2 11222

Direct Detection and Mapping of Star Forming Regions in Nearby, Luminous Quasars

We propose to carry out narrow-band emission line imaging observations of 8 quasars at z=3D0.05-0.15 with the WFPC2 ramp filters and with the NICMOS narrow-band filters. We will obtain images in the [O II], [O III], H-beta, and Pa-alpha emission line bands to carry out a series of diagnostic tests aimed at detecting and mapping out star-forming regions in the quasar host galaxies. This direct detection of star-forming regions will confirm indirect indications for star formation in quasar host galaxies. It will provide a crucial test for models of quasar and galaxy evolution, that predict the co-existence of starbursts and “monsters” and will solve the puzzle of why different indicators of star formation give contradictory results. A secondary science goal is to assess suggested correlations between quasar luminosity and the size of the narrow-line region.

WFPC2 11518

Mutual eclipses of a Kuiper belt-satellite system

Ground-based observations two weeks ago strongly suggest that the orbit of the small inner satellite of 2003 EL61, the 5th largest known dwarf planet, is possibly precisely edge-on and thus somewhere in the middle of a ~3 year long cycle of mutual eclipses, occultations, and transits. We anticipate that with another year of ground-based observation we may have sufficient data to accurately predict the times and durations of these events, but by then the events may well be over. If events are indeed occuring, measurement of the timing and depths of such events provides a wealth of precise geometric information for constraining sizes, shapes, orbits, and dynamics of the system.

We propose to obtain 5 quick WFPC2 visits to 2003 EL61 over the ~19 day orbital period of the inner satellite to determine a precise orbit and predict mutual event times. We will instantly (within ~1 day of the end of the observations) make these predictions public to allow the maximum number of attempts to collect the data as possible.

WFPC2/NIC3 11209

Determining the Structural Parameters of the First Globular Cluster Found to Host an Black-Hole X-ray Binary

We recently published the discovery of the first black hole X-ray binary in a globular cluster. This object is located in a bright globular cluster around the Virgo elliptical NGC 4472. Here we propose to obtain HST PC images of this black- hole hosting globular cluster and a sample of other NGC 4472 globulars. We will use these data to determine the structural parameters of both the globular cluster known to have a black hole and a control sample of other NGC 4472 clusters. This will test recent theoretical predictions how black holes affect the structural parameters of globular clusters, and more generally will allow for the first time constraints on any relationship between the presence of a black hole and the surface brightness profiles of globular clusters. The deep WFPC2 images outside of the galaxy’s central regions will also be invaluable for studying how the sizes and luminosity function of globular clusters depend on distance from the center of the galaxy, and thus address questions about the origin of the size differences between metal-rich and metal-poor clusters and the shape of the globular cluster luminosity function. In addition, parallel NIC3 images will allow the optical to near-infrared colors of NGC 4472 globular cluster to be determined over a wide range of galactocentric radii.


Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.)

HSTARS: (None)

COMPLETED OPS REQUEST: 18233-0 – Clear ACS Event Flag # 2 for OBS # 11163 @ 134/1534z =20 COMPLETED OPS NOTES: (None)

                       SCHEDULED      SUCCESSFUL
FGS GSacq               05                   05
FGS REacq               10                   10
OBAD with Maneuver      30                   30


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