Status Report

NASA Hubble Space Telescope Daily Report # 3552

By SpaceRef Editor
February 18, 2004
Filed under , ,

HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science




NIC1/NIC2/NIC3 9996

Flats Stability

This calibration proposal is the Cycle 12 NICMOS bi-monthly monitor A series
camera 1, 2, & 3 flat fields will be obtained to monitor the health of the

NIC1/NIC2/NIC3 9993

Cycle 12 NICMOS dark current, shading profile, and read noise monitoring

The purpose of this proposal is to monitor the dark current, read noise, and
shading profile for all three NICMOS detectors throughout the duration of
12. This proposal is an essentially unchanged continuation of PID 9636 which
cover the duration of Cycle 11.

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
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
we will measure for the first time: beginlistosetlength sep0cm
setlength opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em
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
effects dominate the power spectrum, providing a test of the gravitational
instability paradigm for structure formation. Measurements on these scales
not possible from the ground, because of the systematic effects induced by
smearing from seeing. Having many independent lines of sight reduces the
uncertainty due to cosmic variance, making parallel observations ideal.


Ozone, Condensates, and Dust in the Martian Atmosphere

We propose to utilize the unique UV capabilities of STIS and ACS/HRC in
order to
study the spatial and seasonal variations in ozone, condensates, and dust
in the
Martian atmosphere. The data obtained will be critical in addressing recent
breakthroughs in understanding the basic radiative, transport, and
processes that provide for both long-term and short-term balance within the
global Mars climate system. The proposal includes both Cycle 11 & 12
observations in order to span the classic dust storm season on Mars and
the first good opportunity for HST to observe a dusty atmosphere on the
The UV observations will complement visible and IR observations that will be
made during the Mars Global Surveyor Extended Mission and will provide
for the future UV observations of MARCI on the 2005 Mars Reconnaissance

FGS 9971

FGS Astrometry of a Star Hosting an Extrasolar Planet: The Mass of Upsilon
Andromedae d

We propose observations with HST/FGS to determine the astrometric elements
{perturbation orbit semimajor axis and inclination} produced by the
extra-solar planet orbiting the F8V star Upsilon Andromedae. These
will permit us to determine the actual mass of the planet by providing the
presently unknown sin i factor intrinsic to the radial velocity method which
discovered this object. An inclination, i = 30degrees, within the range of
very low precision determination using reanalyzed HIPPARCOS intermediate
products, would produce the observed radial velocity amplitude, K = 66 ms
with a
companion mass of ~8 M_Jupiter. Such a mass would induce in Upsilon
Andromedae a
perturbation semi-major axis, Alpha = 0arcs0012, easily within the reach of
HST/FGS fringe tracking astrometry. The proposed observations will yield a
planetary mass, rather than, as previous investigations have done, only
a planetary mass companion.

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
candidate extra-solar planet around the K2 V star Epsilon Eridani that has
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
These data represent a combination of six independent data sets taken with
different telescopes. A least squares orbital solution using robust
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
An estimate of the inclination yields a perturbation semi-major axis, Alpha
0arcs0022, easily within the reach of HST/FGS astrometry.


The Morphological, Photometric, and Spectroscopic Properties of Intermediate
Redshift Cluster Galaxies:

New and fundamental constraints on the evolutionary state of high redshift
clusters will be made by obtaining deep, multiband images {SDSS r, i, z}
the central 1.5 Mpc regions of seven distant clusters in the range 0.76 < z
1.27. The ACS data will allow us to {1} definitively establish the
composition and star formation rates as functions of clustercentric radius,
local density, x-ray luminosity {obtained from accompanying Chandra, and XMM
data}, {2} explore the relationship between substructure, kinematics, and
morphology, {3} strongly constrain the galaxy merger frequency and the
of elliptical and S0 galaxies, {4} measure the mass distribution
from the light {via gravitational lensing} enabling comparisons with
kinematically derived masses, and {5} study the evolution of the structure
the brightest cluster members. The clusters selected for this program
have extensive spectroscopic observations and NIR imaging is either in hand
underway from approved ground based programs. To date, the lower part of
redshift range has only been marginally studied with HST. Our sample
the two most distant, spectroscopically confirmed superclusters and will
significantly increase the baseline over which evolutionary effects can be
studied. The data will also be used to identify very high-z galaxies via
unique spectral properties.

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
usually determined from globular clusters. However, it is alternatively
to determine ages of extreme Population II subgiants in the solar
based on trigonometric parallaxes, without any recourse to clusters. This
approach completely avoids the vexing issues of cluster distances,
and chemical compositions. There are 3 known nearby, extremely
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
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
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
these three Pop II subgiants using HST’s Fine Guidance Sensor 1R. We expect
reduce the Hipparcos parallax error bars by factors of 5-6, providing the
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
major new constraint on the distance scale of globular clusters, with wide
implications for stellar evolution and the calibration of Pop II standard

NIC/NIC3 9865

The NICMOS Parallel Observing Program

We propose to continue managing the NICMOS pure parallel program. Based on
experience, we are well prepared to make optimal use of the parallel
opportunities. The improved sensitivity and efficiency of our observations
substantially increase the number of line-emitting galaxies detected. As our
previous work has demonstrated, the most frequently detected line is Halpha
0.7<z<1.9, which provides an excellent measure of current star formation
We will also detect star-forming and active galaxies in other redshift
using other emission lines. The grism observations will produce by far the
available Halpha luminosity functions over the crucial–but poorly
observed–redshift range where galaxies appear to have assembled most of
stellar mass. This key process of galaxy evolution needs to be studied with
data; we found that observations at shorter wavelengths appear to have
missed a
large fraction of the star-formation in galaxies, due to dust reddening. We
also obtain deep F110W and F160W images, to examine the space densities and
morphologies of faint red galaxies. In addition to carrying out the public
parallels, we will make the fully reduced and calibrated images and spectra
available on-line, with some ground-based data for the deepest parallel

ACS/WFC 9860

ESSENCE: Measuring the Dark Energy Equation of State

The accelerating universe appears to be dominated by a dark energy with a
significant negative pressure. The ratio of the pressure to density of this
mysterious energy {its equation of state} is an observable which can
differentiate between the proliferating candidate theories. We propose to
estimate the dark energy equation of state by observing Type Ia supernovae
redshifts near z=0.7 with HST in concert with the on-going ESSENCE NOAO
program that is discovering and studying supernovae between 0.3<z<0.8. We
that an interesting constraint on the equation of state can be made with
supernovae observed at modest redshifts given the current knowledge of the
matter density. We will follow 10 Type Ia supernovae discovered from the
and passed to HST without disrupting its schedule. The full data set will
constrain the equation of state to 10% and strictly limit the range of
dark energy models. In keeping with the ESSENCE policy, these observations
available to the community immediately.


Anomalous Flux Ratios in Quadruple Gravitationally Lensed QSOs

We propose to observe eight {8} gravitationally lensed systems which exhibit
quadruple images of the background high redshift quasars. Models invoking a
smooth potential fit the observed image positions accurately, in most cases
better than 5 milliarcseconds. But the same models dramatically fail to
the observed flux ratios. These anomalous flux ratios can be attributed to
micro- or milli-lensing in the massive lensing halo. In this proposal, we
isolate the source of the anomalous flux ratios by using the superior
of HST/STIS to obtain spectrophotometric data and compare the emission line
ratio of the QSOs to the continuum flux ratios. Due to the much larger size
the broad emission line regions, the flux ratios in the emission lines
only be affected by milli-lensing if the sub-halos are comparable or larger
projected size than the source region. That is, flux ratios observed in the
continuum are senstive to substructure on all scales {both micro- and
milli-lensing}, while the broad emission lines are insensitive to
due to the larger physical size of the source emission region. This sample
eight quasars will provide the definitive evidence to distinguish between
possible sources causing the observed anomalous flux ratios.

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
nuclear light from each image, thus yielding a "nucleus-free" image of the
galaxy. This will allow investigation of host-galaxy properties: our
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
to estimate black-hole masses of large samples of distant AGNs, correct
determination of the slope of this relationship is critically important.


A SNAPSHOT Survey of Sharp-Lined Early B-Type Stars

Although spectrum synthesis studies of the UV spectra of sharp-lined main
sequence B stars provide us with some our best determinations of the
of the Fe group and neutron capture elements and the chemical evolution in
galaxy and the Magellanic Clouds, the HST archive is virtually devoid of
resolution spectra of the bright nearby B stars that have become to be
as abundance standards. For example, there are NO observations of HR 1886,
Her, and tau Her, the sharpest-lined representatives {V sin i < 5 km/s} of
spectral classes B1 V, B3 IV-V and B5 IV, and only a few tiny spectral
of gamma Peg {B2 IV}. Information on the abundances of the Fe group is
for computing opacities for stellar evolution calculations and for
astrophysical f-values. There are no suitable galactic standards in the HST
database to compare with recent HST/STIS observations of B stars in the
Magellanic Clouds and the likely future observations of similar objects in
and other nearby galaxies. To correct this deficiency, we propose SNAPSHOT
observations with the STIS E140M and E230M gratings of 33 of the best bright
abundance standards in nearby clusters and the galactic field. Using this
we will determine the abundances of the Fe group and heavy elements using
technique of spectrum synthesis with LTE and NLTE treatments. We waive the
proprietary period.

NIC1 9833

T Dwarf Companions: Searching for the Coldest Brown Dwarfs

Faint companions to known stars have historically led to the discovery of
classes of stellar and substellar objects. Because these discoveries are
typically limited by the flux ratio of the components in the system, the
intrinsically faintest companions are most effectively identified around the
intrinsically faintest primaries. We propose to use NICMOS to image a sample
22 of the coolest known {T-type} brown dwarfs in the Solar Neighborhood in
to search for fainter and cooler brown dwarf companions. The high spatial
resolution of the NIC 1 detector enables us to distinguish binary systems
apparent separations greater than 0"08, or physical separations greater
than 1.2
AU at the nominal distances of the objects in our sample. Furthermore, the
substantial sensitivity of NICMOS imaging allows us to probe companion
masses of
5-50 Jupiter masses and companion effective temperatures of 250-1300 K in a
maximally efficient manner. Based on work to date, we expect that roughly
20% of
the objects in our sample will be binary, and that one or two of these will
likely harbor a significantly fainter secondary. Hence, we expect to find a
companion cooler than any currently known brown dwarf, a potential
prototype for
the next spectral class. In addition, our investigation will add
to the sample of known binary brown dwarfs, allowing improved statistical
analyses of the binary fraction, separation distribution, and mass ratio
distribution of these systems, key quantities for probing brown dwarf
We will also identify optimal substellar systems for astrometric mass
measurements, a critical check for theoretical models of brown dwarfs and
extrasolar planets.

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
optical gratings of STIS. The library will be roughly equally divided among
metallicities, very low {[Fe/H] lt -1.5}, low {[Fe/H] -1.5 to -0.5},
{[Fe/H] -0.3 to 0.1}, and super-solar {[Fe/H] gt 0.2}, well-sampling the
HR-diagram in each bin. Such a library will surpass all extant compilations
have lasting archival value, well into the Next Generation Space Telescope
Because of the universal utility and community-broad nature of this venture,
waive the entire proprietary period.

NIC1 9749

NICMOS Observations of the Gl 164 Companion

We propose to image an astrometrically-detected companion of Gl 164. The
companion was discovered with the Stellar Planet Survey {STEPS} instrument
operating on the Palomar 200" telescope. The mass of the companion is
to be ~40 Jupiter masses or more placing it in the brown dwarf range. If we
detect this companion with NICMOS and confirm its nature, we will have one
the few direct measurements of the mass of a brown dwarf.

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
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
to have been formed at 5.8 MY and 8.3 MY ago in catastrophic impact events.
is the first time such precise and young ages have been assigned to a
Main-belt binaries are almost certainly produced by collisions, and we would
expect a young family to have a significantly higher frequency of binaries
the background, because they may not yet have been destroyed by impact or
longer-term gravitational instabilities. In fact, one of the prime
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
by our ground-based discoveries of satellites among larger asteroids}, can
validated and calibrated. HST is the only facility that can be used to
for binaries among such faint objects {V>17.5}. We will also measure two
clusters, one being an "old" family, and the other a collection of
asteroids that do not have a family association, and further compare with
determined value for the frequency of large main-belt binaries {2%}. We
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
of the early solar system, the internal structure of distant ice-rock
and even the genesis of the Pluto-Charon binary. Within the past 18 months,
KBO satellite systems have been discovered, allowing for the first time the
possibility of characterizing a sample of KBO satellite orbital properties.
propose HRC observations to determine satellite orbits in the 6 best cases.
have carefully devised a strategy for each of these 6 systems to make
use of ground-based observations, previous HST observations, and the
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.
strategy relies heavily on extensive Monte Carlo simulations to define
times of observing such that each new point obtained gives maximum leverage
refining the orbital solution. We find that with this strategy we can
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
output with optimal use of scarce resources.

ACS/WFC 9744

HST Imaging of Gravitational Lenses

Gravitational lenses offer unique opportunities to study cosmology, dark
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
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
luminosity, color and structure, and search for lensed images of the source
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
images of 16 lenses never observed by HST in the IR. As in previous cycles,
request that the data be made public immediately.

WFPC2 9740

CIII] Imagery of Planetary Nebulae and HII Regions — A Snap Program

We propose to undertake a SNAP program of WFPC2 imagery of several planetary
nebulae and extragalactic HII regions with the F185W filter to study the
variation of the CIII] 1909 Angstrom emission lines across the nebulae. Much
our current knowledge of carbon abundances in planetary nebulae and HII
are based on UV spectroscopic observations of this line yet there have not
any studies of its spatial variations in nebulae compared to several of the
prominent optical lines {e.g. [OIII] 5007 Angstroms}. Such observations,
with photoionization modeling of the nebulae, will enable us to assess the
utility of using the CIII] line in abundance calculations of C/O and C/H in
nebulae and possibly permit improved empirical emission-line diagnostic
techniques for ionization corrections to get the elemental carbon abundances
from C++/O++ observations based on CIII]/[OIII] 1909/5007. We also plan to
the spatial variation of the CIII] 1909 Angstrom collisionally excited lines
against the CII 4267 Angstrom permitted line in many of the nebulae using
previous and planned ground-based longslit echelle spectroscopy coupled
with the
HST WFPC2 F185W imagery.

NIC1 9737

A NICMOS direct imaging search for giant planets around the seven single
dwarfs in the Hyades

We propose to use the NIC1 camera on HST to search for massive giant planets
around the known seven single white dwarfs in the nearby Hyades cluster at
sub-arcsec separations. At an age of 625 Myr, the white dwarfs had
masses of about 3 solar masses, and massive gaseous giant planets should
formed in the massive circumstellar disks around these ex Herbig A0 stars,
probably at orbital separations similar or slightly larger than that of
{5 AU} in our own solar system. Such planets would have survived the
Sequence mass loss of the parent star, and would have migrated outward
adiabatically by a factor 4.5, equal to the ratio of initial to final
mass {3Mo/0.66Mo}, due to conservation of orbital angular momentum during
mass loss {AGB and PN} phase. Thus the orbital separation NOW would be 4.5 x
AU = 22.5 AU, which at the distance of the Hyades {45 pc} corresponds to
arcsec. Simulations with TinyTim then show that giant planets at this
with masses in the range 6-12 Jupiter masses and apparent J and H magnitudes
the range 20.5-23.3 mag {from Baraffe or Burrows models} can be spatially
resolved around the Hyades white dwarfs. Their J and H brightnesses are
known to
be 15 +/- 0.5 mag, implying a median star-planet brightness ratio of 1000:1
mag}. This combination of dynamic range and orbital separation is observable
with NICMOS, by subtracting images taken at two roll angles. Therefore, the
proposed near-IR diffraction-limited observations in the F110W and F160W
promise to resolve giant planets around low-mass stars for the first time.
successful, the observations would also prove that giant planets do form
early-type stars more massive than the Sun.


Towards a global understanding of accretion physics – Clues from an UV
spectroscopic survey of cataclysmic variables

Accretion inflows and outflows are fundamental phenomena in a wide variety
astrophysical environments, such as Young Stellar Objects, galactic
and AGN. Observationally, cataclysmic variables {CVs} are particularly well
suited for the study of accretion processes. We are currently carrying out a
Cycle 11 STIS UV spectroscopic snapshot survey of CVs to fully exploit the
diagnostic potential of these objects for our understanding of accretion
physics. While the data obtained so far are of excellent quality, the number
targets that will be observed in Cycle 11 is too small for a statistically
significant analysis {only 19 objects out of our 149 accepted Cycle 11
targets have been observed at the time of writing}. We propose here to
this survey into Cycle 12, building a homogenous database of accretion disc
wind outflow spectra covering a wide range of mass transfer rates and binary
inclinations. We will analyze these spectra with state-of-the-art accretion
model spectra {SYNDISK}, testing our current knowledge of the accretion disc
structure, and, thereby, providing new insight into the so far not well
understood process of viscous dissipation. We will use our parameterised
model PYTHON for the analysis of the radiation driven accretion disc wind
spectra, assessing the fundamental question whether the mass loss rate
correlates with the disc luminosity. In addition, our survey data will
a number of systems in which the white dwarf significantly contributes to
the UV
flux, permitting an analysis of the impact of mass accretion on the
evolution of
these compact stars. This survey will triple the number of currently
high-quality accretion disc / wind outflow / accreting white dwarf spectra,
we waive our proprietary rights to permit a timely use of this database.

WFPC2 9712

Pure Parallel Near-UV Observations with WFPC2 within High-Latitude ACS

In anticipation of the allocation of ACS high-latitude imaging survey{s}, we
request a modification of the default pure parallel program for those WFPC2
parallels that fall within the ACS survey field. Rather than duplicate the
bands which will be done much better with ACS, we propose to observe in the
near-ultraviolet F300W filter. These data will enable study of the
ultraviolet morphology of galaxies at 0<z<1. We will determine the
k-correction, and the location of star formation within galaxies, using a
that is likely to be nearly complete with multi-wavelength photometry and
spectroscopic redshifts. The results can be used to interpret observations
higher redshift galaxies by ACS.

ACS/WFC 9701

ACS Default {Archival} Pure Parallel Program II

The proposal is designed to test ACS pure parallels in POMS.

STIS 9633

STIS parallel archive proposal – Nearby Galaxies – Imaging and Spectroscopy

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


Connecting the UV and X-ray Warm Absorbers in NGC 5548

In the last Chandra cycle, we were awarded a joint Chandra/HST proposal to
the warm absorber in NGC 5548 and to obtain a definitive answer about the
connection between the warm absorber and the UV absorber in this object. We
confident that the deep Chandra observation {500 ksec} will allow for an
unprecedented determination of the kinematic components in the warm absorber
well as accurate column density measurements from several line series.
two new lines of investigation that appeared after the submission of the
Chandra/HST proposal, suggest that the original modest request for HST time
not suffice to obtain reliable column density measurements for the UV
In view of the new evidence, we need a a higher S/N in the proposed
to allow for accurate UV column densities determination. Absorption features
both the UV and warm absorbers are known to be variable. Therefore, it will
highly unfortunate if the large investment of Chandra time will not be
accompanied by enough simultaneous HST time to ensure an accurate
of the UV absorber. Without these it will be very difficult to draw
concerning the relationship between the two absorbers. We therefore ask for
additional STIS E140M Echelle orbits.

ACS/WFPC2 9488

Cosmic Shear – with ACS Pure Parallel Observations

The ACS, with greater sensitivity and sky coverage, will extend our ability
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
{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,
particular the galaxy orientations and axis ratios, are such that any
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
unbiased estimates of cosmic shear from a large number of fields, each of
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
existing MDS WFPC2 maximum likelihood galaxy image analysis algorithms to
with the ACS. The analysis would also yield an online database similar to

ACS 9482

ACS Pure Parallel Lyman-Alpha Emission Survey {APPLES}

Ly-alpha line emission is an efficient tool for identifying young galaxies
high redshift, because it is strong in galaxies with young stars and little
no dust — properties expected in galaxies undergoing their first burst of
star- formation. Slitless spectroscopy with the ACS Wide-Field Camera and
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
yet. Parallel observations will allow this survey to be conducted with
impact on HST resources, and we will place reduced images and extracted
in the public domain within three months of observation. We aim to find ~
Ly-alpha emitters, 5 times the biggest current sample of Ly-alpha emitters.
unprecedented sample will provide robust statistics on the populations and
evolution of Ly-alpha emitters between redshifts 4–7; a robust measurement
the reionization redshift completely independent of the Gunn-Peterson
spatial clustering information for Ly-alpha emitters which would let us
their bias function and hence halo mass as a function of redshift; many
at redshift exceeding 6; and lower redshift serendipitous discoveries.


Resolved halo stellar populations in the Milky Way analogue edge-on galaxy

The stellar halo is one of the fundamental building blocks of galaxies.
ground-based surface photometry has shown that stellar halos exist in some
spiral galaxies, with colours similar to those of the main disk, little else
known about their stellar populations. We propose to carry out a systematic
study of the halo regions of the edge-on galaxy NGC 891. The resulting deep
colour-magnitude diagrams will be used to infer the mean metallicity of the
bright halo giants at the tip of the RGB and below, and its metallicity
Recently, Zepf et al. {2000} inferred that the halo metallicity of NGC 5907
to be low {Fe/H <= -1.7}, with a large stellar M/L ratio. We will be able to
test this hypothesis with much better and deeper data. If we can confirm a
similar halo composition in NGC 891, this would imply that the Milky Way
might be very different from external halos. Since galactic halos trace the
history of galaxy formation, this will have important implications for our
understanding of galactic evolution on cosmological time scales. Using these
survey data, we will be able to conclusively distinguish between genuine
objects and merger remnants, without having to assume a scenario in which
halo field population is fully mixed. Surprisingly, such studies have not
been undertaken for NGC 891, although the galaxy is a prime Milky Way


NICMOS Post-SAA calibration – CR Persistence Part 2

A new procedure proposed to alleviate the CR-persistence problem of NICMOS.
frames will be obtained immediately upon exiting the SAA contour 23, and
time a NICMOS exposure is scheduled within 50 minutes of coming out of the
The darks will be obtained in parallel in all three NICMOS Cameras. The
darks will be non-standard reference files available to users with a
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
in addition to the date, because HST crosses the SAA ~8 times per day so
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
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
remove the CR persistence from the science images. Each observation will
its own CRMAP, as different SAA passages leave different imprints on the

STIS/CCD 10091

Soft X-ray Transient in Mira AB

Chandra Observations of Mira AB symbiotic-like system obtained in Dec. 2003
detected an unexpected bright soft source {<0.7 keV} in addition to the
previously observed harder {1-4 keV} emission which has been attributed to
accretion disk around Mira B. The newly discovered soft X-ray source could
indicate an instability in the accretion disk, an accretion related outburst
the system, or a flare-like activity in Mira A. We request DD time to carry
HST/STIS imaging and spectroscopy of Mira AB at UV wavelengths, where
of these processes are very likely to be found. Because of the likely
nature of this phenomenon, timely HST observations are critical for
the nature and the characteristics of the soft X-ray source and therefore we
cannot wait for Cucle 13 observatios including TOO observations.

WFPC2 10090

WFII backup parallel archive proposal

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

STIS/CCD 10085

STIS Pure Parallel Imaging Program: Cycle 12

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

WFPC2 10084

WFII parallel archive proposal

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

WFPC2 10082

POMS Test Proposal: WFII backup parallel archive proposal

This is a POMS test proposal designed to simulate scientific plans

WFPC2 10070

WFPC2 CYCLE 12 Supplemental Darks Part 2/3

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


CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
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/WFC 10056

Extreme Red Stars

ACS provides unprecedented sensitivity in the far red, this coupled with
astronomical pushes to ever cooler objects {e.g. new classifications for L
and T
stellar dwarfs, and extremely high redshift galaxies} increases the need for
extending the photometric calibration to include such objects. We propose
observations of 2 stellar objects for which STIS spectra will exist, as well
NICMOS grism. The two targets include a late M dwarf and a T dwarf. The M
provides a temporal check with WFC and new constraint for the HRC. The T
provides new results for the WFC.

ACS/WFC 10054

ACS photometric Stability

A set of four spectrophotometric standard stars {GD71, G191B2B, GD153, and
is observed once with ACS’s WFC and HRC through all filters, except the ramp
filters, to assess the sensitivity of the instrument and measure accurate
photometric zero points. The stars are placed at the centre of the
aperture, and
two images are taken through each filter. This programme is based on
9020 and 9654 designed for SMOV and Cycle 11, and also on programme 9563
the interim period. No RAMP filters are calibrated here. The exposure times
been calculated to reach, on average, SNR~350 in the central pixel for broad
band filters.


Stability of the ACS CCD: Flat fielding, Photometry, Geometry

This program will verify that the low frequency flat fielding, the
and the geometric distortion are stable in time and across the field of view
the CCD detectors. A moderately crowded stellar field, located ~6′ West of
center of the cluster 47 Tuc, is observed every three months with the WFC
HRC using the full suite of broad and narrow band filters. The same field
been observed during SMOV to derive low frequency corrections to the ground
flats and to create a master catalogue of positions and magnitudes from
observations of the cluster. In Cycle 11, this field was observed again
single pointings at various roll angles. The positions and magnitudes of
are used to monitor local and large scale variations in the plate scale and
sensitivity of the detectors. The Cycle 12 program will continue to monitor
these effects and will derive an independent measure of the detector CTE.

STIS/MA1 10034

Cycle 12 MAMA Dark Monitor

This test performs the routine monitoring of the MAMA detector dark noise.
proposal will provide the primary means of checking on health of the MAMA
detectors systems through frequent monitoring of the background count rate.
purpose is to look for evidence of change in dark indicative of detector

STIS/CCD 10019

CCD Bias Monitor – Part 1

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

STIS/CCD 10017

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD.

NIC3 10014

Spectrophotometry of FAINT IR STANDARDS

Faint spectrophotometric standard stars required for COS and the SBC channel
ACS have been established via the STIS FASTEX program that has executed
over the
last three cycles. Cycle 12 is an especially opportune time to establish
companion faint IR standards for WFC3, because the NICMOS proposal 9998
observations in cycle 12 of all 6 of the primary standard stars in order to
establish the absolute flux calibration of the three grism modes to 1%. In
addition to WFC3, these new faint secondary IR standards will be a
step towards establishing flux standards for JWST, as well as for SNAP,
and SOFIA. The 6 primary standards included in Propid=9998 are in the range
V=11-13 and include three hot pure hydrogen WDs and 3 solar analogs. We
to establish new IR faint standards in the 15-17 mag range. Appropriate
types for faint IR standards are solar analogs and hotter WDs. Many M type
cooler stars are variable, so that long term monitoring is required before
committing HST time to such cool stars. A few G type and WD faint stars will
provide a set of faint IR standards with minimal sky and color coverage.
Existing HST images of any candidates can provide verification that there
are no
contaminating stars above the 1% level within 2-3arcsec. However, the ACS
calibration field in 47 Tuc is too crowded for linking to ground based
observations. If the other candidates are selected from SDSS or other ground
based data, then the NICMOS and STIS acquisition images can provide this
verification, as well as correction factors for arbitrary photometric size
apertures. The SNAP team is providing the northern faint stars using
SDSS data. In addition, the extreme coolest types such as L and T stars have
proven essential to sorting out the long wavelength QE of ACS; both the ACS
eventually WFC3 calibrations could be improved with knowledge of L and T
SEDs in
the region beyond 0.95 microns. In addition to the primary purpose of ACS
QE vs.
wavelength and broad band F814W and F850LP calibrations, these three stars
C.} below are at the flux level required for WFC3 grism calibration. The
brighter M, L, and T standard stars will each require a NICMOS orbit, while
faint standard requires two Nicmos orbits and one STIS orbit for complete
wavelength coverage. The STIS spectra of the M and L stars are done as ACS
calibrations in cycles 12 and 11, respectively. An additional faint WD has
already been proposed for 2 Nicmos and 4 STIS orbits in their cycle 12
already. See Table 1 for a summary of the 18 orbit allocation for this
10014. Bright stars in the V=0-6 mag range would be useful for direct
comparisons to NIST calibrated lamps. This comparison would offer the
opportunity to compare two fundamentally different realms of physics: pure
hydrogen stellar models and laboratory black body physics. Unfortunately,
Nicmos bright limit is V=~8 for a solar analog and a 1s exposure without
defocussing the OTA. The primary Sloan standard BD+17d4708 at V=9.9 is
fainter than this Nicmos limit.

ACS/WFC 10009

Galactic Bulge Deep Survey

We propose a deep survey in the second lowest extinction {after Baade’s
region in the galactic bulge, the window identified by Stanek {1998} at l, b
~0.25, -2.1. This will complement our deep HST/Chandra survey of Baade’s
carried out in July 2003 and allow comparative source populations, and
constraints on the gradient towards the galactic center, to be derived.
Nine HST
orbits are requested to do the optical identifications in this field down to
~ 9, sufficient to identify most CVs and qLMXBs. This will constrain the
object populations in the galactic bulge.


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

HSTAR 9323: GS Acquisition (1,2,1) @ 046/17:49:12Z resulted in FL backup
FGS 1 due to SSLE (QF2SSLEX) on FGS 2. Prior FHST
FM Updates @ 046/17:43:42Z
and 17:46:27Z showed good attitude error vector.
Under investigation.



  • 1200-0 Raise Bay 5 Limit @ 045/1915z
  • 1194-0 Adjust Recharge Ratio Limits for High Sun DOY 2004/036-046 @045/0700z
  • 0900-1 COMMAND PROBLEM @ 046/1742z
  • 0916-0 Tabulation of Slew Attitude Error (Miss-distance) @ 047/0533z
  • 1199-1 Adjust ACS Error Count Limit @ 047/1832z
  • 1201-0 Change Limits MAMA2 Threshold Voltage @ 047/1942z
  • 1199-2 Adjust ACS Error Count Limit @ 048/0300z
  • 0911-0 Limit Management During WFPC2 Decontamination (M001) @ 048/0957z

                           SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq               41                        41
FGS REacq               19                        19
FHST Update             85                         85


SpaceRef staff editor.