Status Report

HST Daily Report # 3298

By SpaceRef Editor
February 11, 2003
Filed under , ,

HUBBLE SPACE TELESCOPE

DAILY REPORT # 3298

PERIOD COVERED: DOY 41

OBSERVATIONS SCHEDULED

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.

STIS/CCD 9066

Closing in on the Hydrogen Reionization Edge of the Universe.

The Space Telescope Imaging Spectrograph (CCD) was used in parallel
constrain
the Hydrogen reionization edge in emission that marks the transition from
a
neutral to a fully ionized IGM at a predicted redshifts.

WF/PC-2 9157

Fundamental Properties Of L-Type Dwarfs In Binaries.

The goal is to obtain astrometric, photometric and spectroscopic
measurements of
each component that will yield basic information on atmospheric and
dynamical
properties.

FGS 9348

The Distances to AM CVn stars

We propose to determine the parallaxes and proper motions of the five
brightest
of the seven known AM CVn systems using the HST Fine Guidance Sensors. AM
CVn
systems are binaries where mass is transferred from a completely
hydrogen-deficient, degenerate mass donor to a white dwarf primary
through a
helium accretion disk. A better understanding of these systems is crucial
for a
number of reasons:, to study the late stages of binary evolution, to
study the
effect of chemical composition on the physics of accretion discs; , o to
estimate their contribution to the Supernovae Ia rate and , to estimate
their
contribution to the gravitational radiation background. All these studies
rely
critically on a determination of the distances to the currently known
systems.
With brightnesses in the range 13<V<17 and estimated distances <400pc
they are
ideal targets for the HST-FGS.

ACS 9352

The Deceleration Test from Treasury Type Ia Supernovae at Redshifts 1.2
to 1.6

Type Ia supernovae {SNe Ia} provide the only direct evidence for an
accelerating
universe, an extraordinary result that needs a rigorous test. The case
for
cosmic acceleration rests on the observation that SNe Ia at z ~ 0.5 are ~
0.25
mag fainter than they would be in a universe without acceleration. A
powerful
and straightforward way to assess the reliability of the SN Ia
measurement and
the conceptual framework of its interpretation is to look for cosmic
deceleration at z >= 1. This would be a clear signature of a mixed
dark-matter
and dark-energy universe. Systematic errors in the SN Ia result
attributed to
grey dust or cosmic evolution of the SN Ia peak luminosity would not show
this
change of sign. We have demonstrated proof of this concept with a single
SN Ia,
SN 1997ff at z = 1.7, found and followed by HST. The results suggest an
early
epoch of deceleration, but this is too important a conclusion to rest on
just
one object. Here we propose to use HST for observations of six SNe Ia in
the
range 1.2 <= z <= 1.6, that will be discovered as a byproduct from
proposed
Treasury programs for high-latitude ACS surveys. Six objects will provide
a
much
firmer foundation for a conclusion that touches on important questions of
fundamental physics.

STIS/CCD/MA1 9357

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 of
astrophysical environments, such as Young Stellar Objects, galactic
binaries,
and AGN. Observationally, cataclysmic variables {CVs} are particularly
well
suited for the study of accretion processes. We propose to carry out a
STIS UV
spectroscopic snapshot survey of CVs that fully exploits the diagnostic
potential of these objects for our understanding of accretion physics.
This
survey will provide an homogenous database of accretion disc and 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 disc 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 wind 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 identify 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 at least double, if not triple, the number of
high-quality accretion disc / wind outflow / accreting white dwarf
spectra, and
we waive our proprietary rights to permit a timely use of this database.

STIS/CCD 9378

Galaxy Dynamics at Very Large Radius using LyAlpha Absorption Lines

We propose to investigate the outer dynamics of the nearby spiral galaxy
NGC1398
at very large galactocentric radii by using the kinematical information
from
Ly-alpha absorption lines in the spectra of 3 background UV-bright
objects {two
Seyferts 1 and one QSO}. It is a unique opportunity to have 3 UV-bright
objects
surrounding one single isolated spiral galaxy, and this will enable us to
measure its disk rotation up to radii several times greater than what is
possible in HI at 21cm, since the UV-bright objects lie at projected
distances
of ~ 80 to 270 kpc. At these large radii we expect to observe the turn
down
from
flat rotation, and be able to determine the size of the dark matter halo
and
hence measure the total mass and mass-to-light ratio of a spiral galaxy.

NICMOS/STIS CCD 9405

The Origin of Gamma-Ray Bursts

The rapid and accurate localization of gamma-ray bursts {GRBs} promised
by a
working HETE-2 during the coming year may well revolutionize our ability
to
study these enigmatic, highly luminous transients. We propose a program
of HST
and Chandra observations to capitalize on this extraordinary opportunity.
We
will perform some of the most stringent tests yet of the standard model,
in
which GRBs represent collimated relativistic outflows from collapsing
massive
stars. NICMOS imaging and STIS CCD spectroscopy will detect broad atomic
features of supernovae underlying GRB optical transients, at luminosities
more
than three times fainter than SN 1998bw. UV, optical, and X-ray
spectroscopy
will be used to study the local ISM around the GRB. Chandra spectroscopy
will
investigate whether the GRB X-ray lines are from metals freshly ripped
from the
stellar core by the GRB. HST and CTIO infra-red imaging of the GRBs and
their
hosts will be used to determine whether `dark’ bursts are the product of
unusually strong local extinction; imaging studies may for the first time
locate
the hosts of `short’ GRBs. Our early polarimetry and late-time broadband
imaging
will further test physical models of the relativistic blast wave that
produces
the bright GRB afterglow, and will provide unique insight into the
influence of
the GRB environment on the afterglow.

ACS 9472

A Snapshot Survey for Gravitational Lenses among z >= 4.0 Quasars

Over the last few years, the Sloan Digital Sky Survey has revolutionized
the
study of high-redshift quasars by discovering over 200 objects with
redshift
greater than 4.0, more than doubling the number known in this redshift
interval.
The sample includes eight of the ten highest redshift quasars known. We
propose
a snapshot imaging survey of a well-defined sample of 250 z > 4.0 quasars
in
order to find objects which are gravitationally lensed. Lensing models
including
magnification bias predict that at least 4% of quasars in a flux-limited
sample
at z > 4 will be multiply lensed. Therefore this survey should find of
order 10
lensed quasars at high redshift; only one gravitationally lensed quasar
is
currently known at z > 4. This survey will provide by far the best sample
to
date of high-redshift gravitational lenses. The observed fraction of
lenses can
put strong constraints on cosmological models, in particular on the
cosmological
constant Lambda. In addition, magnification bias can significantly bias
estimates of the luminosity function of quasars and the evolution
thereof; this
work will constrain how important an effect this is, and thereby give us
a
better understanding of the evolution of quasars and black holes at early
epochs, as well as constrain models for black hole formation.

ACS 9480

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/WFPC2 9481

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

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 red
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
rest-frame
ultraviolet morphology of galaxies at 0<z<1. We will determine the
morphological
k-correction, and the location of star formation within galaxies, using a
sample
that is likely to be nearly complete with multi-wavelength photometry and
spectroscopic redshifts. The results can be used to interpret
observations of
higher redshift galaxies by ACS.

NICMOS 9484

The NICMOS Parallel Observing Program

We propose to manage the default set of pure parallels with NICMOS. Our
experience with both our GO NICMOS parallel program and the public
parallel
NICMOS programs in cycle 7 prepared us to make optimal use of the
parallel
opportunities. The NICMOS G141 grism remains the most powerful survey
tool for
HAlpha emission-line galaxies at cosmologically interesting redshifts. It
is
particularly well suited to addressing two key uncertainties regarding
the
global history of star formation: the peak rate of star formation in the
relatively unexplored but critical 1<= z <= 2 epoch, and the amount of
star
formation missing from UV continuum-based estimates due to high
extinction. Our
proposed deep G141 exposures will increase the sample of known HAlpha
emission-
line objects at z ~ 1.3 by roughly an order of magnitude. We will also
obtain a
mix of F110W and F160W images along random sight-lines to examine the
space
density and morphologies of the reddest galaxies. The nature of the
extremely
red galaxies remains unclear and our program of imaging and grism
spectroscopy
provides unique information regarding both the incidence of obscured star
bursts and
the build up of stellar mass at intermediate redshifts. In addition to
carrying out the parallel program
we will populate a public database with calibrated spectra and images,
and
provide limited ground- based optical and near-IR data for the deepest
parallel
fields.

ACS/WFC 9584

ACS Default {Archival} Pure Parallel Program II.

The Advanced Camera for Surveys (WFC) was used to test ACS pure
parallels.

WFPC2 9589

WFPC2 Decontaminations and Associated Observations Pt. 1/3

This proposal is for the monthly WFPC2 decons. Also included are
instrument
monitors tied to decons: photometric stability check, focus monitor, pre-
and
post-decon internals {bias, intflats, kspots, & darks}, UV throughput
check,
VISFLAT sweep, and internal UV flat check.

WFPC2 9592

WFPC2 CYCLE 11 Standard Darks

This dark calibration program obtains dark frames every week in order to
provide
data for the ongoing calibration of the CCD dark current rate, and to
monitor
and characterize the evolution of hot pixels. Over an extended period
these
data
will also provide a monitor of radiation damage to the CCDs.

WFPC2 9594

WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt2/3

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

WFPC2 9596

WFPC2 CYCLE 11 INTERNAL MONITOR

This calibration proposal is the Cycle 11 routine internal monitor for
WFPC2, to
be run weekly to monitor the health of the cameras. A variety of internal
exposures are obtained in order to provide a monitor of the integrity of
the CCD
camera electronics in both bays {gain 7 and gain 15}, a test for quantum
efficiency in the CCDs, and a monitor for possible buildup of
contaminants on
the CCD windows.

STIS 9605

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD

STIS 9607

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 1×1
at gain = 4, to build up high-S/N superbiases and track the evolution of
hot
columns.

ACS 9649

ACS internal CTE monitor

The charge transfer efficiency {CTE} of the ACS CCD detectors will
decline as
damage due to on-orbit radiation exposure accumulates. This degradation
will be
closely monitored at regular intervals, because it is likely to determine
the
useful lifetime of the CCDs. All the data for this program is acquired
using
internal targets {lamps} only, so all of the exposures should be taken
during
Earth occultation time {but not during SAA passages}. This program
emulates the
ACS pre-flight ground calibration and post-launch SMOV testing {program
8948},
so that results from each epoch can be directly compared. Extended Pixel
Edge
Response {EPER} and First Pixel Response {FPR} data will be obtained over
a
range of signal levels for both the Wide Field Channel {WFC}, and the
High
Resolution Channel {HRC}.

ACS 9673

CCD Daily Monitor

for any source of noise in ACS CCD detectors. This programme will be
executed
once a day for the entire lifetime of ACS

WFPC2 9676

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.

STIS 9706

STIS Pure Parallel Imaging Program: Cycle 10

This is the default archival pure parallel program for STIS during cycle
10.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.) None

COMPLETED OPS REQs:
NONE

OPS NOTES EXECUTED:
1072-1† ND2ARETI Low Limit Adjust @ 042/20:25

                         SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq              8                         8
FGS REacq              7                         7
FHST Update            16                       16
LOSS of LOCK

SIGNIFICANT EVENTS:
CCS "B" String Command Timing Test scheduled 042/11:00Z – 21:00Z with
GDOC,
SOC HITT,
and CCS using CCS "B" String with CCS Release 4.0.2. Purpose of this
testing is to
verify CCS Release 4.0.2 Command Timing.

SpaceRef staff editor.