Daily 3433

HUBBLE SPACE TELESCOPE

DAILY REPORT        # 3433

PERIOD COVERED: DOYs 234-236

OBSERVATIONS SCHEDULED

ACS 9984

Cosmic Shear With ACS Pure Parallels

Small distortions in the shapes of background galaxies by foreground
mass provide a powerful method of directly measuring the amount and
distribution of dark matter. Several groups have recently detected
this weak lensing by large-scale structure, also called cosmic shear.
The high resolution and sensitivity of HST/ACS provide a unique
opportunity to measure cosmic shear accurately on small scales. Using
260 parallel orbits in Sloan textiti {F775W} we will measure for the
first time: beginlistosetlength sep0cm setlengthemsep0cm setlength
opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em the
skewness of the shear distribution, and em the magnification effect.
endlist Our measurements will determine the amplitude of the mass
power spectrum sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20,
and the mass density Omega_m with s/n=4. They will be done at small
angular scales where non-linear effects dominate the power spectrum,
providing a test of the gravitational instability paradigm for
structure formation. Measurements on these scales are not possible
from the ground, because of the systematic effects induced by PSF
smearing from seeing. Having many independent lines of sight reduces
the uncertainty due to cosmic variance, making parallel observations
ideal.

ACS/HRC 9976

The Parallaxes and Proper Motions of Two Nearby Neutron Stars

We propose to measure the parallax of two nearby neutron stars to the
highest possible level of accuracy, ~.0.5 mas. The primary goal is to
determine the neutron-star radius at infinity with better than 1 km
precision, and therewith obtain a direct constraint on the equation of
state of matter at supra-nuclear density. The required flux and
temperature determinations are easiest for the so-called isolated or
radio-quiet neutron stars because of their apparently completely
thermal spectrum. We argue that the importance of the possible results
warrants a study to the best possible level of the best possible
sources, and request 24 orbits for the two brightest isolated neutron
stars, RX J1856.5-3754 and RX J0720.4-3125. We will also determine
whether the enigmatic RX J0720.4-3125 is an old magnetar or an
accreting source, based on its luminosity and proper motion.

FGS 9969

FGS Astrometry of the Extrasolar Planet of Epsilon Eridani

We propose observations with HST/FGS in Position Mode to determine the
astrometric elements {perturbation orbit semimajor axis and
inclination} of the candidate extra-solar planet around the K2 V star
Epsilon Eridani that has been detected by Doppler spectroscopy. These
observations will also permit us to determine the actual mass of the
planet by providing the sin{i} factor which can not be determined with
the radial velocity method. High precision radial velocity {RV}
measurements spanning the years 1980.8--2000.0 for the nearby {3.22
pc} star Epsilon Eri show convincing variations with a period of ~ 7
yrs. These data represent a combination of six independent data sets
taken with four different telescopes. A least squares orbital solution
using robust estimation yields orbital parameters of period, P = 6.9
yrs, velocity K- amplitude = 19 m/s, eccentricity e = 0.6, projected
companion mass M_B sin{i} = 0.83 M_Jupiter. An estimate of the
inclination yields a perturbation semi-major axis, Alpha = 0arcs0022,
easily within the reach of HST/FGS astrometry.

ACS/WFC/HRC 9908

Evolution of Scaling Relations of Field Spiral Galaxies at Intermediate
Redshift

We seek imaging of the William Herschel Deep Field {WHDF} with the ACS
to primarily determine morphological and structural parameters of a
sample of 94 late-type galaxies brighter than R=23 with redshifts up
to z=1. We already obtained spectra of the galaxies at ESO's VLT from
which spatially resolved rotation curves are derived. Only the
combined VLT and ACS data allows us the construction of the
Tully-Fisher Relation {TFR} at intermediate redshift. Together with 77
galaxies from the FORS Deep Field {FDF}, for which we already have ACS
determined structural parameters, we will have the hitherto largest
kinematic sample to investigate significantly the evolution of the TFR
and the Fundamental Plane of spiral galaxies. The additional WHDF
galaxies populate mainly both ends of the TFR {i.e. are slow rotators
or bright early-type giants} being indispensable for the verification
of an evolving slope as suggested by the FDF sample. Such a difference
in the luminosity and mass evolution between dwarf and giant galaxies
is a strong constraint to current theories of galaxy formation and
evolution. The ACS imaging of the WHDF will boost its scientific
impact also with other investigations like the study of the
Fundamental Plane of intermediate redshift field elliptical galaxies,
the study of the size and type evolution of an even larger sample of
galaxies and the study of galaxy-galaxy lensing.

ACS/WFC 9891

A snapshot survey of rich stellar clusters in the Large and Small
Magellanic Clouds

Rich stellar clusters are vital to a wide variety of astrophysical
research, from stellar evolution studies to the formation and
evolution of galaxies. In this context, it is important to understand
how rich star clusters form and evolve. The cluster systems in the LMC
and SMC are particularly important in achieving this, because they are
the only systems which contain clusters at all stages of evolution
while being close enough to be studied as fully resolved stellar
populations - although in general this requires the capabilities of
HST. We have recently investigated the structural evolution of LMC and
SMC clusters using archival WFPC2 data, and demonstrated a dramatic
trend in the sizes of these clusters with age. We have shown that this
trend likely represents genuine structural evolution in these
clusters, although it is not clear whether we are observing a
dynamical process or the signature of changing formation conditions.
This result has implications for all astronomical research involving
massive stellar clusters. To develop this work further requires the
extension of our two samples, so that they are statistically
quantifiable. This will allow a number of key questions regarding the
structural evolution trend to be answered. We propose a two-colour
ACS/WFC SNAP survey of rich Magellanic Cloud clusters to achieve this
aim. The unique resolution and sensitivity of ACS/WFC is required for
success, because of the crowded nature of the targets. The SNAP data
will have a large number of additional applications, both to globular
cluster and Magellanic Cloud research.

FGS 9883

Parallaxes of Extreme Halo Subgiants: Calibrating Globular Cluster
Distances and the Ages of the Oldest Stars

The ages of the oldest stars are a key constraint on the evolution of
our Galaxy, the history of star formation, and cosmological models.
These ages are usually determined from globular clusters. However, it
is alternatively possible to determine ages of extreme Population II
subgiants in the solar neighborhood based on trigonometric parallaxes,
without any recourse to clusters. This approach completely avoids the
vexing issues of cluster distances, reddenings, and chemical
compositions. There are 3 known nearby, extremely metal-deficient Pop
II subgiants with Hipparcos parallax errors of 6-11% which are
available for such age determinations. At present, based on the latest
isochrones, the derived ages of these stars {HD 84937, HD 132475, and
HD 140283} are all close to 14 Gyr, uncomfortably close to or higher
than current estimates of the age of the universe. However, the errors
in the Hipparcos parallaxes imply uncertainties of at least 2 Gyr in
the ages of the 3 stars. We propose to measure parallaxes of these
three Pop II subgiants using HST's Fine Guidance Sensor 1R. We expect
to reduce the Hipparcos parallax error bars by factors of 5-6,
providing the most stringent test yet of current theoretical stellar
models of Pop II stars and pushing the age uncertainties to below 0.5
Gyr. These data will also provide a major new constraint on the
distance scale of globular clusters, with wide implications for
stellar evolution and the calibration of Pop II standard candles.

ACS/HRC 9851

Host Galaxies of Reverberation-Mapped AGNs

We propose to obtain unsaturated ACS high-resolution images of all
reverberation-mapped active galactic nuclei in order to remove the
point-like nuclear light from each image, thus yielding a
"nucleus-free" image of the host galaxy. This will allow investigation
of host-galaxy properties: our particular interest is determination of
the host-galaxy starlight contribution to the reverberation mapping
observations, which is necessary for accurate determination of the
relationship between the AGN continuum flux and the size of the broad
Balmer-line emitting region of AGNs. Because this relationship is used
to estimate black-hole masses of large samples of distant AGNs,
correct determination of the slope of this relationship is critically
important.

ACS/HRC 9823

Rings of Uranus: Dynamics, Particle Properties and Shepherding Moons

We propose to image the rings and small inner satellites of Uranus
using the High Resolution Channel of the ACS. The revolutionary
capabilities of the ACS will allow us to address a variety of
important questions relating to ring properties and ring-moon
interactions. Observations at a range of wavelengths and phase angles
will reveal the opposition surges of these rings and moons, providing
information on color and surface structure. Measurements of the ring
in front of the planet will provide complementary information on
optical depth; any variations of optical depth with wavelength will
reveal the rings' poorly-constrained population of embedded dust. The
rings of Uranus are closing rapidly as the planet approaches equinox
in 2007, an event that takes place only every 42 years. Using this
opportunity, our observations will be repeated at different solar and
terrestrial tilt angles; this sequence of images will be particularly
valuable for constraining the physical thickness and packing density
of the rings. We will place particular emphasis on the rotational
variations of the Epsilon Ring, whose radial width {and therefore its
packing density} varies by a factor of five. In addition, a set of
deep exposures targeted just off the planet will enable us to detect
any 4-5 km moons embedded within the ring system. Dynamicists invoke
numerous such moons to "shepherd" the many sharp ring boundaries, so
this will serve as a definitive test of the theory.

STIS 9786

The Next Generation Spectral Library

We propose to continue the Cycle 10 snapshot program to produce a Next
Generation Spectral Library of 600 stars for use in modeling the
integrated light of galaxies and clusters. This program is using the
low dispersion UV and optical gratings of STIS. The library will be
roughly equally divided among four metallicities, very low {[Fe/H] lt
-1.5}, low {[Fe/H] -1.5 to -0.5}, near-solar {[Fe/H] -0.3 to 0.1}, and
super-solar {[Fe/H] gt 0.2}, well-sampling the entire HR-diagram in
each bin. Such a library will surpass all extant compilations and have
lasting archival value, well into the Next Generation Space Telescope
era. Because of the universal utility and community-broad nature of
this venture, we waive the entire proprietary period.

ACS/HRC/WFC 9764

Elliptical galaxies in z~1.5 clusters

Giant elliptical galaxies offer can some of the tightest constraints
on models of galaxy formation. Recent observations have shown
significant inconsistencies between their properties and the
predictions of the currently popular hierarchical clustering models.
Many outstanding questions about the nature and evolution of these
objects can best {or only} be addressed by extending studies of
cluster ellipticals out to z>1. Recently we have identified large
overdensities of red galaxies, strongly clustered around powerful
radio sources at z~1.5. We propose to image our two richest fields, of
Abell Class 0-1 richness, using the F814W and F606W filters on the
ACS/WFC. Our goals are to investigate: {1} Galaxy morphologies: we
will determine the bulge fractions of the red cluster galaxies, to
confirm that they are early-types, and measure their characteristic
radii to investigate their evolutionary status. {2} Colour gradients:
we will search for colour gradients indicative of recent star
formation {particularly blue cores}, or inhomogeneities in the
internal colours which might be indicative of recent assembly. {3}
Cluster membership: with two additional colours we will obtain
accurate photometric redshift estimates for all galaxies. Combined
with studies of nearby clusters and of field ellipticals, our results
will place very tight constraints on the formation of the most massive
galaxies.

ACS/HRC 9747

An Imaging Survey of the Statistical Frequency of Binaries Among
Exceptionally-Young Dynamical Families in the Main Asteroid Belt

We propose an ambitious SNAPSHOT program to determine the frequency of
binaries among two very young asteroid families in the Main Belt, with
potentially profound implications. These families {of C- and S-type}
have recently been discovered {Nesvorny et al. 2002, Nature 417, 720},
through dynamical modeling, to have been formed at 5.8 MY and 8.3 MY
ago in catastrophic impact events. This is the first time such precise
and young ages have been assigned to a family. Main-belt binaries are
almost certainly produced by collisions, and we would expect a young
family to have a significantly higher frequency of binaries than the
background, because they may not yet have been destroyed by impact or
longer-term gravitational instabilities. In fact, one of the prime
observables from such an event should be the propensity for
satellites. This is the best way that new numerical models for binary
production by collisions {motivated largely by our ground-based
discoveries of satellites among larger asteroids}, can be validated
and calibrated. HST is the only facility that can be used to search
for binaries among such faint objects {V>17.5}. We will also measure
two control clusters, one being an "old" family, and the other a
collection of background asteroids that do not have a family
association, and further compare with our determined value for the
frequency of large main-belt binaries {2%}. We request visits to 180
targets, using ACS/HRC.

ACS/HRC 9746

Binary systems in the Kuiper Belt

The properties of the orbits of Kuiper belt object {KBO} satellites
hold keys to fundamental insight into masses and densities of KBOs,
the interaction history of the early solar system, the internal
structure of distant ice-rock bodies, and even the genesis of the
Pluto-Charon binary. Within the past 18 months, 9 KBO satellite
systems have been discovered, allowing for the first time the
possibility of characterizing a sample of KBO satellite orbital
properties. We propose HRC observations to determine satellite orbits
in the 6 best cases. We have carefully devised a strategy for each of
these 6 systems to make maximum use of ground-based observations,
previous HST observations, and the smallest possible number of new HST
observations. Our proposed observations will efficiently provide
highly reliable orbital solutions which are critical to achieving the
scientific promise available from the study of these systems. Our
strategy relies heavily on extensive Monte Carlo simulations to define
optimal times of observing such that each new point obtained gives
maximum leverage for refining the orbital solution. We find that with
this strategy we can provide mass solutions for all 6 systems to an
accuracy of better than 10% using only 25 new HST observations. This
highly efficient program provides extreme scientific output with
optimal use of scarce resources.

ACS/WFC 9744

HST Imaging of Gravitational Lenses

Gravitational lenses offer unique opportunities to study cosmology,
dark matter, galactic structure, galaxy evolution and quasar host
galaxies. They are also the only sample of galaxies selected based on
their mass rather than their luminosity or surface brightness. While
gravitational lenses can be discovered with ground-based optical and
radio observations, converting them into astrophysical tools requires
HST. HST has demonstrated that it is the only telescope that can in
each case precisely locate the lens galaxy, measure its luminosity,
color and structure, and search for lensed images of the source host
galaxy given the typical image separations of ~1''. We will obtain
ACS/WFC V and I images and NICMOS H images of 21 new lenses never
observed by HST and NICMOS H images of 16 lenses never observed by HST
in the IR. As in previous cycles, we request that the data be made
public immediately.

NIC1/NIC2/STIS/CCD/WFPC2 9738

Spectroscopy and Polarimetry of Mars at Closest Approach

We plan a coordinated program of spectroscopy, imaging, and
spectropolarimetry of Mars during the August 2003 opposition to study
the composition and physical state of surface materials and airborne
aerosols. The observations include {a} Moderate spectral resolution
290 to 570 nm STIS long-slit push-broom imaging spectroscopy of Mars,
to constrain the properties of airborne aerosol particles and to
search for and globally map iron-bearing minerals that are diagnostic
of specific past climatic conditions; {b} WFPC2 UV-VIS images designed
primarily to quantify the effects of ice and dust aerosols on our STIS
spectra; {c} NICMOS near-IR images to search for and globally map the
presence of hydrated surface minerals; and {d} ACS multispectral
polarizer images to provide critical phase function measurements
needed to constrain the physical properties of the Martian surface
layer. The observations are timed to take advantage of the closest
approach of Mars to Earth for the next several hundred years. Images
and spectra will be acquired at a spatial scale comparable to existing
spacecraft orbital spectroscopy data {~10 km/pixel} and in wavelength
regions not sampled by past or current Mars spacecraft
instrumentation. These observations also provide complementary
scientific and calibration measurements in support of current and
future NASA and ESA Mars exploration missions.

WFPC2 9710

POMS Test Proposal: WFII backup parallel archive proposal

This is a POMS test proposal designed to simulate scientific plans.

WFPC2 9709

POMS Test Proposal: WFII parallel archive proposal

This is the generic target version of the WFPC2 Archival Pure Parallel
program. The program will be used to take parallel images of random
areas of the sky, following the recommendations of the 2002 Parallels
Working Group.

ACS 9675

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.

ACS/STIS 9664

SDSS Primary Standards

The ACS HRC and WFC cameras have Sloan Digital Sky Survey standard
filters, the first use of these on HST. Calibration of the u, g, r, i,
z filters in ACS will be obtained in order to assure that observers
can place HST and SDSS observations on a common system. The SDSS has
adopted the 10th magnitude star, BD+17D4708 as their fundamental
reference. STIS calibration spectra of this will be obtained over the
full 0.2-1.0+ micron range covered by G230LB, G430L and G750L in order
to generate a reference spectrum of this star in the HST system in
order for SYNPHOT to generate robust synthetic magnitudes {the STIS
observations are through the STIS program, 9631, Bohlin PI}. ACS
observations will be obtained through the SDSS filters in order to
reference u, g, r, i, z photometry to the same fundamental standard
used by SDSS. In addition, since this will become a useful additional
standard star, we will also obtain observations through the full suite
of ACS UV-optical filters in order to assist photometric
transformations between different systems

ACS/WFC 9648

External CTE Monitor

Monitor CTE changes during cycle 11. Determine CTE

WFPC2 9634

POMS Test Proposal: WFII targeted parallel archive proposal

The parallel opportunities available with WFPC2 in the neighborhood of
bright galaxies are treated in a slightly different way from the
normal pure parallels. Local Group galaxies offer the opportunity for
a closer look at young stellar populations. Narrow-band images in
F656N can be used both to identify young stars via their emission
lines, and to map the gas distribution in star-forming regions. Thus,
the filter F656N is added to the four standard filters. Near more
distant galaxies, up to about 10 Mpc, we can map the population of
globular clusters; for this purpose, F300W is less useful, and only
F450W, F606W, and F814W will be used.

STIS 9633

STIS parallel archive proposal - Nearby Galaxies - Imaging and
Spectroscopy

Using parallel opportunities with STIS which were not allocated by the
TAC, we propose to obtain deep STIS imagery with both the Clear
{50CCD} and Long-Pass {F28X50LP} filters in order to make
color-magnitude diagrams and luminosity functions for nearby galaxies.
For local group galaxies, we also include G750L slitless spectroscopy
to search for e.g., Carbon stars, late M giants and S-type stars. This
survey will be useful to study the star formation histories, chemical
evolution, and distances to these galaxies. These data will be placed
immediately into the Hubble Data Archive.

STIS 9621

CCD Sparse-Field CTE External C11

This program will allow the derivation of accurate coefficients which
can be used to correct low count level data {both imaging and
spectroscopy} for nonlinearity/CTE effects. Dependences on x-position,
background sky level, and time dependence will be quantified in
addition to accurate determination of intensity and y-position effects
in a third epoch and to higher accuracy than previously determined.
With these corrections the effect of CTE can be calibrated in order
that no Sscience data should have additional induced photometry errors
in excess of 1%.

STIS 9608

CCD Bias Monitor - Part 2

Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1,
and 1x1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.

STIS 9606

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

WFPC2 9595

WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt3/3

This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels.

ACS/WFPC2 9488

Cosmic Shear - with ACS Pure Parallel Observations

The ACS, with greater sensitivity and sky coverage, will extend our
ability to measure the weak gravitational lensing of galaxy images
caused by the large scale distribution of dark matter. We propose to
use the ACS in pure parallel {non- proprietary} mode, following the
guidelines of the ACS Default Pure Parallel Program. Using the HST
Medium Deep Survey WFPC2 database we have measured cosmic shear at
arc-min angular scales. The MDS image parameters, in particular the
galaxy orientations and axis ratios, are such that any residual
corrections due to errors in the PSF or jitter are much smaller than
the measured signal. This situation is in stark contrast with
ground-based observations. We have also developed a statistical
analysis procedure to derive unbiased estimates of cosmic shear from a
large number of fields, each of which has a very small number of
galaxies. We have therefore set the stage for measurements with the
ACS at fainter apparent magnitudes and smaller, 10 arc-second scales
corresponding to larger cosmological distances. We will adapt existing
MDS WFPC2 maximum likelihood galaxy image analysis algorithms to work
with the ACS. The analysis would also yield an online database similar
to that in archive.stsci.edu/mds/

ACS 9482

ACS Pure Parallel Lyman-Alpha Emission Survey {APPLES}

Ly-alpha line emission is an efficient tool for identifying young
galaxies at high redshift, because it is strong in galaxies with young
stars and little or no dust --- properties expected in galaxies
undergoing their first burst of star- formation. Slitless spectroscopy
with the ACS Wide-Field Camera and G800L grism allows an unmatched
search efficiency for such objects over the uninterrupted range 4 <~ z
<~ 7. We propose the ACS Pure Parallel Ly-alpha Emission Survey
{``APPLES''}, to exploit this unique HST capability and so obtain the
largest and most uniform sample of high redshift Ly-alpha emitters
yet. Parallel observations will allow this survey to be conducted with
minimal impact on HST resources, and we will place reduced images and
extracted spectra in the public domain within three months of
observation. We aim to find ~ 1000 Ly-alpha emitters, 5 times the
biggest current sample of Ly-alpha emitters. This unprecedented sample
will provide robust statistics on the populations and evolution of
Ly-alpha emitters between redshifts 4--7; a robust measurement of the
reionization redshift completely independent of the Gunn-Peterson
trough; spatial clustering information for Ly-alpha emitters which
would let us probe their bias function and hence halo mass as a
function of redshift; many galaxies at redshift exceeding 6; and lower
redshift serendipitous discoveries.

STIS 9383

Probing the Grains Responsible for Extinction Using Small Magellanic
Cloud Sightlines

Small Magellanic Cloud sightlines have the greatest potential to
relate specific interstellar extinction features to distinct grain
properties. The reasons for this are 1} prominent extinction features
such as the 2175 Angstrom bump and the far-ultraviolet rise vary among
SMC targets and 2} grain types may be very different from those in the
Galaxy. Specifically, Welty et al. {2001} recently identified an SMC
sightline that contains dust, but no silicate grains. Silicates are a
dominant source of extinction in all dust models; the SMC may be the
only location where the importance of silicates can be verified or
disproved. We propose to explore the relationship between grain types
and extinction toward 2 SMC stars with very different extinction
curves; AzV 18 lacks a 2175 Angstrom bump and has a strong far-UV rise
while the extinction curve towards the SMC star AzV 456 has a
prominent 2175 Angstrom bump and a much weaker far-UV rise. We will
compare the interstellar abundances of atoms that are prevalent in
silicates {Si, Mg, Fe} toward these 2 stars and use the results to
constrain dust extinction models. These SMC observations, which can
only be obtained with STIS, are the only direct way to probe the
connection between grain types/environments and extinction. The
results from this study will be useful for modeling and understanding
all regions that contain dust {AGN, circumstellar disks, star
formation regions, etc.}.

STIS/CCD 10000

STIS Pure Parallel Imaging Program: Cycle 12

This is the default archival pure parallel program for STIS during
cycle 12.

FLIGHT OPERATIONS SUMMARY:

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

HSTAR 9123:  GS Acquisition (3,1,1) @ 235/11:46:34Z failed to gyr
control after 3                        attempt and FGS 3. Under
investigation.

COMPLETED OPS REQs: NONE

OPS NOTES EXECUTED:
1095-6  Consolidated PCS Limit Modifications @ 234/19:29z
1047-0  Adjust Recharge Ratio Limits for High Sun DOY 2003/235-241 @
235/06:07z
1048-0  Adjust ACS Error Count Limit @ 235/15:23z

                           SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq               28                        27             See
Hstar
# 9123
FGS REacq               07                        07
FHST Update             50                        50
LOSS of LOCK

SIGNIFICANT EVENTS: None