Daily #3989

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 3989

PERIOD COVERED: UT November 15, 2005 (DOY 319)

OBSERVATIONS SCHEDULED

ACS/HRC 10556

Neutral Gas at Redshift z=0.5

Damped Lyman-alpha systems {DLAs} are used to track the bulk of the
neutral hydrogen gas in the Universe. Prior to HST UV spectroscopy,
they could only be studied from the ground at redshifts z1.65.
However, HST has now permitted us to discover 41 DLAs at z1.65 in our
previous surveys. Followup studies of these systems are providing a
wealth of information about the evolution of the neutral gas phase
component of the Universe. But one problem is that these 41
low-redshift systems are spread over a wide range of redshifts
spanning nearly 70% of the age of the Universe. Consequently, past
surveys for low-redshift DLAs have not been able to offer very good
precision in any small redshift regime. Here we propose an ACS-HRC-
PR200L spectroscopic survey in the redshift interval z=[0.37, 0.7]
which we estimate will permit us to discover another 41 DLAs. This
will not only allow us to double the number of low-redshift DLAs, but
it will also provide a relatively high-precision regime in the
low-redshift Universe that can be used to anchor evolutionary studies.
Fortunately DLAs have high absorption equivalent width, so
ACS-HRC-PR200L has high-enough resoultion to perform this proposed
MgII-selected DLA survey.

ACS/WFC 10496

Decelerating and Dustfree: Efficient Dark Energy Studies with
Supernovae and Clusters

We propose a novel HST approach to obtain a dramatically more useful
"dust free" Type Ia supernovae {SNe Ia} dataset than available with
the previous GOODS searches. Moreover, this approach provides a
strikingly more efficient search-and-follow-up that is primarily pre-
scheduled. The resulting dark energy measurements do not share the
major systematic uncertainty at these redshifts, that of the
extinction correction with a prior. By targeting massive galaxy
clusters at z 1 we obtain a five-times higher efficiency in
detection of Type Ia supernovae in ellipticals, providing a
well-understood host galaxy environment. These same deep cluster
images then also yield fundamental calibrations required for future
weak lensing and Sunyaev-Zel'dovich measurements of dark energy, as
well as an entire program of cluster studies. The data will make
possible a factor of two improvement on supernova constraints on dark
energy time variation, and much larger improvement in systematic
uncertainty. They will provide both a cluster dataset and a SN Ia
dataset that will be a longstanding scientific resource.

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 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/NIC3 10541

Probing the jet mattter content of quasar PKS 0637-752

The matter content {electron-proton vs electron-positron composition}
of extragalactic jets remains unknown, despite over three decades of
work. Here, we propose NICMOS/NIC3 and ACS observations of the
Chandra-detected, one sided jet of the superluminal quasar PKS 0637-
752 to derive the jet matter content by measuring the component of the
Cosmic Microwave Background {CMB} radiation that is bulk-Comptonized
{BC} by the cold electrons in the relativistically flowing large scale
jet. What makes this source particularly suited for this procedure, is
the absence of significant non-thermal jet emission from the 'bridge',
the region between the core and the first bright knot WK7.8,
guaranteeing that most of the electrons in the bridge are cold,
leaving the BC scattered CMB radiation as the only significant source
of photons in this region. The proposed NICMOS and ACS observations of
the knot WK7.8 will provide spectral information in the IR-UV regime,
which, together with existing multiwavelength data, will be used to
derive the jet Doppler factor and minimum power necessary to power the
knot emission as a function of the jet matter content. These will in
turn be used to deduce, or strongly constrain, the actual jet matter
content through comparison with the proposed NICMOS observations of
the BC 'bridge' emission.

FGS 10610

Astrometric Masses of Extrasolar Planets and Brown Dwarfs

We propose observations with HST/FGS to estimate the astrometric
elements {perturbation orbit semi-major axis and inclination} of
extra-solar planets orbiting six stars. These companions were
originally detected by radial velocity techniques. We have
demonstrated that FGS astrometry of even a short segment of reflex
motion, when combined with extensive radial velocity information, can
yield useful inclination information {McArthur et al. 2004}, allowing
us to determine companion masses. Extrasolar planet masses assist in
two ongoing research frontiers. First, they provide useful boundary
conditions for models of planetary formation and evolution of
planetary systems. Second, knowing that a star in fact has a plantary
mass companion, increases the value of that system to future
extrasolar planet observation missions such as SIM PlanetQuest, TPF,
and GAIA.

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.

S/C/NIC1 10724

NICMOS Focus Monitoring

The purpose of this proposal is to determine the best focus for all
three NICMOS detectors. The program will be executed every ~6 weeks.
Each execution will concern a single detector, except two occasions
which will include NIC3. In total NIC1 and NIC2 will be monitored 4
times each during the current cycle, while NIC3 will only be monitored
twice. The program starts with a focus sweep using only the NIC1
camera {visit 11}. The following observation is with the NIC2 camera
{visit 12} after about 45 days. This pattern is repeated throughout
the period except for Jan 1-8 and Jul 1-8 where also the NIC3 camera
is used. In total this will result in 10 orbits. Notice that VISIT #1
#2 refers to visits for #1 sequential visit number for a given camera
#2 camera in question visit 32 is therefore the third visit for camera
2. Some tweaking of dates and sources are necessary to ensure
visibility under 2-gyro mode. These are the dates and targets for
Cycel14: Visit 11: Oct 01-08 NIC1 NGC1850 Visit 12: Nov 15-22 NIC2
NGC3603 Visit 21: Jan 01-15 NIC1 NGC3603 Visit 13: Jan 01-15 NIC3
NGC3603 Visit 22: Feb 15-22 NIC2 NGC3603 Visit 31: Apr 01-15 NIC1
NGC1850 Visit 32: May 22-31 NIC2 NGC3603 Visit 41: Jun 15-22 NIC1
NGC1850 Visit 23: Jun 15-22 NIC3 NGC1850 Visit 42: Aug 07-22 NIC2
NGC3603

WFPC2 10601

The high proper motion of PSR B0540-69.3

We wish to pin down the proper motion of the Crab-like pulsar PSR
B0540-69.3. HST/WFPC2 archival data have an epoch separation by 4
years which we have already used to obtain a very high transverse
velocity, 1190 +/- 560 km/s. The indicated direction of the proper
motion is consistent with it being along the southern jet of the
pulsar wind nebula. The high velocity could be linked to the high
asymmetry of the supernova ejecta, which suggests a highly asymmetric
supernova explosion. We need a third epoch of HST imaging to test our
present 2-sigma limit. With the suggested observation we will obtain a
1-sigma limit on the transverse motion better than 200 km/s. PSR
B0540-69.3 could be the third young pulsar connected to a supernova
remnant for which a proper motion is established. The other two are
the Crab and Vela pulsars. Both these pulsars have their proper
motions aligned with the jet axis of their pulsar wind nebulae. PSR
B0540-69.3 could thus be the third object {of three} to reveal that it
shares this property. This would provide vital information to
supernova explosion and pulsar kick models. PSR B0540-69.3 would
undoubtedly also be the most distant pulsar ever for which a proper
motion is established.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS: (None)

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSacq 09 09
FGS REacq 02 02
OBAD with Maneuver 22 22

SIGNIFICANT EVENTS: (None)