Date: May 1st 2006

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4103

PERIOD COVERED: UT April 28,29,30, 2006 (DOY 118,119,120)

OBSERVATIONS SCHEDULED

NICMOS 8791

NICMOS Post-SAA calibration - CR Persistence Part 2

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/HRC/WFC 10758

ACS CCDs daily monitor

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 Changes from cycle 13:- The default gain for WFC is 2 e-/DN As before bias frames will be collected for both gain 1 and gain 2 Dark frames are acquired using the default gain {2} This program cover the period May, 31 2006- Oct, 1-2006 The first half of the program has a different proposal number: 10729

NICS3 10754

Spectrophotometric Standards for Cross-Observatory Calibration

This program will obtain NICMOS spectrophotometry of four main sequence A stars and four K giants, each selected from the Spitzer IRAC photometric calibration target and/or candidate calibration target lists These observations will supplement existing HST observations of DA white dwarfs and solar analogs, and will provide a broad base of stellar types for spectrophotometric cross calibration of HST, Spitzer, and eventually JWST The targets are chosen to be faint enough for unsaturated observations with JWST NIRSPEC, yet still bright enough for high signal to noise in relatively short observations with HST+NICMOS and with Spitzer+IRAC

ACS/WFC 10753

An Astrometric Calibration Field Near the Ecliptic Pole

This program will obtain deep ACS astrometry of a Large Magellanic Cloud star field lying within the planned continuous viewing zone of the James Webb Space Telescope, which extends to a 5 degree radius from the Ecliptic pole To allow a full astrometric solution to be calculated, controlling for distortions within ACS that may be time variable over periods of months to years, we will observe our target field at two distinct roll angles separated by approximately 90 degrees To help control for large scale distortions, we will "chop" the observations in at least one roll angle, using offsets of order one third the ACS field of view

NIC3 10728

Flats Stability

This calibration proposal is the Cycle 14 NICMOS flat field monitor program A series of camera 1, 2, & 3 flat fields will be obtained to monitor the health of the cameras

ACS/WFC 10592

An ACS Survey of a Complete Sample of Luminous Infrared Galaxies in the Local Universe

At luminosities above 10^11 4 L_sun, the space density of far-infrared selected galaxies exceeds that of optically selected galaxies These `luminous infrared galaxies' {LIRGs} are primarily interacting or merging disk galaxies undergoing enhanced star formation and Active Galactic Nuclei {AGN} activity, possibly triggered as the objects transform into massive S0 and elliptical merger remnants We propose ACS/WFC imaging of a complete sample of 88 L_IR > 10^11 4 L_sun luminous infrared galaxies in the IRAS Revised Bright Galaxy Sample {RBGS: i e , 60 micron flux density > 5 24 Jy} This sample is ideal not only in its completeness and sample size, but also in the proximity and brightness of the galaxies The superb sensitivity, resolution, and field of view of ACS/WFC on HST enables a unique opportunity to study the detailed structure of galaxies that sample all stages of the merger process Imaging will be done with the F439W and F814W filters {B and I-band} to examine as a function of both luminosity and merger state {i} the evidence at optical wavelengths of star formation and AGN activity and the manner in which instabilities {bars and bridges} in the galaxies may funnel material to these active regions, {ii} the relationship between star formation and AGN activity, and {iii} the structural properties {AGN, bulge, and disk components} and fundamental parameters {effective radius and surface brightness} of LIRGs and their similarity with putative evolutionary byproducts {elliptical, S0 and classical AGN host galaxies} This HST survey will also bridge the wavelength gap between a Spitzer imaging survey {covering seven bands in the 3 6-160 micron range} and a GALEX UV imaging survey of these galaxies, but will resolve complexes of star clusters and multiple nuclei at resolutions well beyond the capabilities of either Spitzer or GALEX The combined datasets will result in the most comprehensive multiwavelength study of interacting and merging galaxies to date

ACS/WFC 10587

Measuring the Mass Dependence of Early-Type Galaxy Structure

We propose two-color ACS-WFC Snapshot observations of a sample of 118 candidate early- type gravitational lens galaxies Our lens-candidate sample is selected to yield {in combination with earlier results} an approximately uniform final distribution of 40 early-type strong lenses across a wide range of masses, with velocity dispersions {a dynamical proxy for mass} ranging from 125 to 300 km/s The proposed program will deliver the first significant sample of low-mass gravitational lenses All of our candidates have known lens and source redshifts from Sloan Digital Sky Survey data, and all are bright enough to permit detailed photometric and stellar- dynamical observation We will constrain the luminous and dark-matter mass profiles of confirmed lenses using lensed-image geometry and lens-galaxy structural/photometric measurements from HST imaging in combination with dynamical measurements from spatially resolved ground-based follow-up spectroscopy Hence we will determine, in unprecedented detail, the dependence of early-type galaxy mass structure and mass-to-light ratio upon galaxy mass These results will allow us to directly test theoretical predictions for halo concentration and star-formation efficiency as a function of mass and for the existence of a cuspy inner dark- matter component, and will illuminate the structural explanation behind the fundamental plane of early-type galaxies The lens-candidate selection and confirmation strategy that we propose has been proven successful for high-mass galaxies by our Cycle 13 Snapshot program {10174} The program that we propose here will produce a complementary and unprecedented lens sample spanning a wide range of lens-galaxy masses

ACS/WFC 10573

Globular Clusters in the Direction of the Inner Galaxy

The age, chemical and kinematic distributions of stellar populations provide powerful constraints on models of the formation and evolution of the Milky Way The globular clusters constitute an especially useful case because the stars within individual clusters are coeval and spatially distinct But a serious limitation in the study of many globular clusters -- especially those located near the Galactic Center -- has been the existence of large absolute and differential extinction by foreground dust We propose to use the ACS to map the differential extinction and remove their effects in a large sample of globular clusters located in the direction of the inner Galaxy using a technique refined recently by von Braun and Mateo {2001} These observations and their analyses will let us produce high quality color-magnitude diagrams of these poorly studied clusters that will allow us to determine these clusters' relative ages, distances and chemistry and to address important questions about the formation and the evolution of the inner Galaxy Our aim for these ACS observations is to obtain data for the most crowded clusters in the inner Galaxy where the excellent spatial resolution of the ACS is most necessary

ACS/SBC 10568

Ultraviolet spectrum of the binary millisecond pulsar J0437-4715

PSR J0437-4715 is the nearest and the brightest millisecond {recycled} pulsar, and the only one detected at near-optical wavelengths We detected it with the HST STIS/FUV-MAMA detector and found that its FUV spectrum is consistent with being emitted from the neutron star surface with a temperature of about 0 1 MK, surprisingly high for such an old object We also found evidence of an emission line at 1372 A, tentatively interpreted as a Zeeman component of the hydrogen Ly-alpha line in a magnetic field of 700 MG Unfortunately, the spectrum was imaged in a region of strong detector background, which strongly hampered the spectral analyses We propose to re-observe the pulsar with the ACS/SBC in FUV and ACS/HRC in NUV to obtain the spectrum of the pulsar in a broad UV range The spectral analysis will allow us to measure the temperature of the full neutron star surface and probe the heating mechanisms operating in old neutron stars Confirmation of the spectral line would lead to a first direct measuremnt of the magnetic field and the radius of a spin-powered neutron star and uniquely constrain the equation of state of superdense matter The NUV spectrum will also probe the magnetospheric emission and the thermal structure of the cool white dwarf companion

ACS/SBC 10554

Globular Cluster Systems of Elliptical Galaxies in Low Density Environments

We propose to use the ACS/WFC to determine colour {metallicity} distributions and luminosity functions for the globular cluster populations in a well-defined sample of elliptical galaxies in low- density environments, and to compare the results with similar samples taken from a rich cluster environment Low-luminosity ellipticals are now recognized to play a pivotal role in testing hierarchical models of galaxy formation, and their globular cluster populations provide a unique probe of their star formation and metal enrichment history The data will be used to {i} determine whether the bimodal colour distributions indicative of multiple formation epochs in luminous ellipticals are also prevalent in low-luminosity field ellipticals; {ii} place joint constraints on age and metallicity in systems with more than one population and determine the spread of ages in any one system; {iii} test whether cluster destruction processes {e g tidal shocking} are more effective in low-luminosity ellipticals, as predicted from their higher mass densities ACS observations are essential to eliminate foreground/background contamination and to probe deep into the luminosity function to obtain a good statistical sample of clusters The TAC has previously awarded HST time to two large surveys of globular cluster systems in rich cluster environments, but there is currently no comparable survey in low-density environments with which to compare these results

ACS/HRC 10549

SAINTS - Supernova 1987A INTensive Survey

SAINTS is a program to observe SN 1987A, the brightest supernova in 384 years, as it morphs into the youngest supernova remnant at age 18 HST is the unique and perfect tool for spatially- resolved observations of the many physical components of SN 1987A A violent encounter is underway between the fastest-moving debris and the circumstellar ring, exciting hotspots seen with HST that are suddenly lighting up The optical and X-ray flux from the ring are both rising rapidly: HST and Chandra observations taken together are needed to understand the physics of these shocked regions In Cycle14, the hotspots may fuse as the shock fully enters the ring Photons from these shocks may excite previously hidden gas outside the ring, revealing the true extent of the mass loss that preceded the explosion The inner debris of the explosion itself, still excited by radioactive isotopes produced in the explosion, is now well resolved by ACS and seen to be aspherical, providing direct clues to the mechanism of the explosion Our search for a compact remnant is beginning to eliminate some theoretical possibilities and we have the opportunity in Cycle 14 to place much more stringent limits with NICMOS Many questions about SN 1987A remain unanswered How did the enigmatic three rings form in the late stages of Sanduleak -69 202? Precisely what took place in the center during the core collapse and bounce? Is a black hole or a neutron star left behind in the debris? SAINTS has been a continuous program since HST was launched-- we propose to extend this rich and deep data set for present use and future reference to answer these central questions in the science of supernovae

ACS/WFC 10523

The Halo Shape and Metallicity of Massive Spiral Galaxies

We propose to resolve the stellar populations of the halos of seven nearby, massive disk galaxies using a SNAP survey with WFC/ACS These observations will provide star counts and color-magnitude diagrams 2-3 magnitudes below the tip of the Red Giant Branch along the two principal axes and one intermediate axis of each galaxy We will measure the metallicity distribution functions and stellar density profiles from star counts down to very low average surface brightnesses, equivalent to ~31 V-mag per square arcsec This proposal will create a unique sampling of galaxy halo properties, as our targets cover a range in galaxy mass, luminosity, inclination, and morphology As function of these galaxy properties this survey will provide:- the first systematic measurement of radial light profiles and axial ratios of the diffuse stellar halos and outer disks of spiral galaxies- a comprehensive analysis of halo metallicity distributions as function of galaxy type and position within the galaxy- an unprecedented study of the stellar metallicity and age distribution in the outer disk regions where the disk truncations occur- the first comparative study of globular clusters and their field stellar populations We will use these fossil records of the galaxy assembly process to test halo formation models within the hierarchical galaxy formation scheme

ACS/WFC 10505

The Onset of Star Formation in the Universe: Constraints from Nearby Isolated Dwarf Galaxies

The details of the early star formation histories of tiny dwarf galaxies can shed light on the role in galaxy formation of the reionization which occured at high redshift Isolated dwarfs are ideal probes since their evolution is not complicated by environmental effects owing to the vicinity of the Milky Way and M31 In addition, dwarf galaxies are the most common type of galaxies, and potentially the building blocks of larger galaxies Since we can date the oldest stars in them, their study represents a complementary approach to the study of the formation and evolution of galaxies through high-z observations We propose to use the ACS to obtain a homogeneus dataset of high-quality photometry, down to the old {13 Gyr} main-sequence turnoffs, for a representative sample of 4 isolated Local Group dwarf galaxies These data are essential to unambiguously determine their early star formation histories, through comparison with synthetic color-magnitude diagrams, and using the constraints provided by their variable stars Parallel WFPC2 observations of their halos will allow us to reveal the actual nature of their stellar population gradients, providing important aditional constraints on their evolution The proposed observations are being complemented with ground-based spectroscopy, to obtain metallicity and kinematic information The observations requested here, which must reach M_I=+3 5 {I=27 5- 28 2} with S/N=10 in crowded systems, can only be achieved with HST using ACS, and won't be possible with planned ground- or space-based facilities such as JWST Based on deep WFPC2 observations and ACS image simulations, our team has designed an observational strategy which carefully considers the optimal filter combination, the necessary photometry depth and the effects of stellar crowding

FLIGHT OPERATIONS SUMMARY:

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

HSTARS: 10244 - GSAcq(2,1,1) failed to (M2G) due to search radius limit exceeded on FGS-2 @ 120/06:11:51z

Upon acquisition of signal at 120/06:23:30 the spacecraft was in RGA control (M2G) The GSAcq(2,1,1) scheduled at 120/05:58:37 -06:06:42 failed to (M2G) due to search radius limit exceeded on FGS-2 Pre-acquisition OBADs both succeded OBAD2 at 120/05:51:55 had attitude correction total (RSS) value of 49 88 arcseconds Primary FGS search radius = 57 arcseconds

10246 - GSAcq(2,1,1) failed to RGA Control @ 120/23:00:16z

The GSAcq(2,1,1) scheduled at 120/23:00:16 - 23:08:21 failed to RGA control due to stop flag (QF2STOPF) on FGS-2 Pre-acquisition OBADs both succeded OBAD2 at 120/22:55:56 had attitude correction total (RSS) value of 8 48 arcseconds

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                    SCHEDULED      SUCCESSFUL      FAILURE TIMES

FGS GSacq 25 23 Hstar # 10244& # 10246 FGS REacq 17 17 OBAD with Maneuver 72 72

SIGNIFICANT EVENTS: (None)

The following information is a reminder of your current mailing list subscription:

You are subscribed to the following list: [list_name]

using the following email: BULK_EMAIL

You may automatically unsubscribe from this list at any time by visiting the following URL:

http://www aus-city com/cgi-bin/dada/mail cgi/u/[list]/

If the above URL is inoperable, make sure that you have copied the entire address Some mail readers will wrap a long URL and thus break this automatic unsubscribe mechanism

You may also change your subscription by visiting this list's main screen:

http://www aus-city com/cgi-bin/dada/mail cgi/list/[list]

If you're still having trouble, please contact the list owner at: