HST Daily Report # 3327

HUBBLE SPACE TELESCOPE

DAILY REPORT # 3327

PERIOD COVERED: DOY 84

OBSERVATIONS SCHEDULED

FLIGHT OPERATIONS SUMMARY:

NICMOS 8791

NICMOS Post-SAA calibration – CR Persistence Part 2

A new procedure proposed to alleviate the CR-persistence problem of NICMOS.
Dark
frames will be obtained immediately upon exiting the SAA contour 23, and
every
time a NICMOS exposure is scheduled within 50 minutes of coming out of the
SAA.
The darks will be obtained in parallel in all three NICMOS Cameras. The
POST-SAA
darks will be non-standard reference files available to users with a
USEAFTER
date/time mark. The keyword ‘USEAFTER=date/time’ will also be added to the
header of each POST-SAA DARK frame. The keyword must be populated with the
time,
in addition to the date, because HST crosses the SAA ~8 times per day so
each
POST-SAA DARK will need to have the appropriate time specified, for users to
identify the ones they need. Both the raw and processed images will be
archived
as POST-SAA DARKSs. Generally we expect that all NICMOS science/calibration
observations started within 50 minutes of leaving an SAA will need such maps
to
remove the CR persistence from the science images. Each observation will
need
its own CRMAP, as different SAA passages leave different imprints on the
NICMOS
detectors.

ACS/HRC 9295

Coronagraphic search for disks around nearby stars

HD 163296 is a Herbig Ae star with a circumstellar disk that was previously
imaged using STIS. It is the source of a bipolar jet that consists of
discrete
knots, also seen in the STIS images. HD 100546 is a Herbig Be star with a
circumstellar disk that was previously imaged using STIS and NICMOS. The
STIS
images show disk-like circumstellar material with a somewhat spiral
structure.
GG Tauri is a young binary {0.25″ separation} that is surrounded by a
circumbinary disk that appears as an inclined ring with a semi-minor axis of
1″
and a semi-major axis of 1.8″. The interior of the disk has been cleared by
tidal forces due to the binary, resulting in the ring-like appearance. A gap
in
the ring is seen in HST and ground- based adaptive optics images. It is
likely a
shadow cast by material between the ring and the stars. WFPC2 images have
revealed material within 0.3″ of the secondary star that might be dust
trapped
at a Lagrangian point {it is too large to be a circumstellar disk}.
Verification
of this material is important as it may influence the illumination of the
outer
ring. The WFPC2 images failed to detect the far side of the ring in F555W
due to
the intrinsic faintness of the ring at that wavelength {due to increased
forward
scattering} and PSF subtraction residuals. The greater sensitivity of the
ACS
and its more stable PSF should provide a definite detection of the far side,
providing important constraints on the relationship between wavelength and
the
scattering phase, as well as possible reddening of the ring caused by
intervening dust.

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.

ACS/HRC 9379

Near Ultraviolet Imaging of Seyfert Galaxies: Understanding the
Starburst-AGN
Connection

We propose a near-UV snapshot survey of 101 Seyfert galaxies using ACS/HRC
and
the filter F330W, a configuration which is optimal to detect faint star
forming
regions around their nuclei. These images will complement optical and
near-IR
images available in the HST archive, thus providing a panchromatic atlas of
the
inner regions of active galaxies, which we will use to study the
starburst-AGN
connection. The main goals of this proposal are: {1} Determine the frequency
of
circumnuclear starbursts in Seyferts, down to levels which cannot be
observed
from the ground; {2} characterize the observational {fluxes, colors,
structure,
sizes} and intrinsic {luminosities, masses, ages, global star-formation
rate}
properties of these clusters; {3} derive the luminosity functions of young
star
clusters around the nucleus of Seyferts and compare these results with those
from normal and starburst galaxies to determine their survival rate close
to the
AGN; {4} address questions about the relation between AGNs and starbursts,
like
the possible connection between the masses and luminosities of black holes
and
starbursts, and the implications for the evolution of the black holes and
their
host galaxy bulges. By adding UV images to the existing optical and near-IR
ones, this project will create an extremely valuable database for
astronomers
with a broad range of scientific interests, from the properties of the AGN
to
the properties of their host galaxies.

STIS 9437

Quantitative Constraints for Massive Star Evolution Models with Rotation

Rotation is now recognized as an important physical component in
understanding
massive stars. Theory suggests that rotation affects the lifetimes, chemical
yields, stellar evolution tracks, and the supernova and compact remnant
properties {Heger & Langer 2000, Maeder & Meynet 2000}. In a Cycle 7
program, we
proved that rotational mixing occurs in massive main sequence stars {Venn
et al.
2001}. In this proposal, we want to quantitatively test model predictions
and
constrain the theory for a better understanding of massive star evolution.
We
are requesting HST STIS observations of the BIII 2066 Angstrom resonance
line of
seven massive stars in three young clusters carefully selected from IUE
analyses. These stars show traces of boron depletion, but without nitrogen
enrichment; rotation is the only theory able to explain this abundance
pattern.
These new abundances will allow us to test rotating model predictions: that
mixing strength increases with stellar age, mass, and rotation rate. They
will
also help to quantitatively constrain the rotational mixing efficiencies in
massive stars. One very high S/N spectrum of a moderately boron-depleted
star is
also requested. We wish to measure its 11B/10B ratio, which is predicted to
change as boron is depleted in the rotating models. This ratio will further
confirm rotational effects and observationally constrain the 10B{p, Alpha}
thermonuclear reaction rate, which is presently highly uncertain.

ACS 9476

Galaxy Evolution in the Richest Clusters at z=0.8: the EDisCS Cluster Sample

The study of distant cluster galaxies requires two key ingredients: {1} deep
high-resolution imaging, to constrain galaxy structure; and {2} 8m-class
spectroscopy, to measure stellar content, star-formation rates, dynamics,
and
cluster membership. We will reach both conditions with the addition of
HST/ACS
imaging to our suite of VLT {36 nights} and NTT {20 nights} observations of
10
confirmed clusters at z~0.8, drawn from the ESO Distant Cluster Survey
{EDisCS}.
The proposed HST/ACS data will complement our existing optical/IR imaging
and
spectroscopy with quantitative measures of cluster galaxy morphologies {i.e.
sizes and shapes, bulge-disk decompositions, asymmetry parameters}, and with
measurements of cluster masses via weak lensing. Major advantages unique to
the
EDisCS project include: {i} uniform selection of clusters; {ii} large enough
sample sizes to characterize the substantial cluster-to-cluster variation in
galaxy populations; {iii} large quantities of high quality data from 8m
telescopes; {iv} uniform measurements of morphologies, spectroscopic and
photometric redshifts, SEDs, star-formation/AGN activities, and internal
kinematics; {v} optical selection of clusters to complement the X-ray
selection
of almost all high-z clusters in the ACS GTO programs; {vi} forefront
numerical
simulations designed specifically to allow physical interpretation of
observed
differences between the high-z and local clusters.

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.

NICMOS 9485

Completing A Near-Infrared Search for Very Low Mass Companions to Stars
within
10 pc of the Sun

Most stars are fainter and less massive than the Sun. Nevertheless, our
knowledge of very low mass {VLM} red dwarfs and their brown dwarf cousins is
quite limited. Unknown are the true luminosity function {LF}, multiplicity
fraction, mass function, and mass-luminosity relation for red and brown
dwarfs,
though they dominate the Galaxy in both numbers and total mass. The best way
to
constrain these relations is a search for faint companions to nearby stars.
Such
a search has several advantages over field surveys, including greater
sensitivity to VLM objects and the availability of precise parallaxes from
which
luminosities and masses can be derived. We propose to complete our
four-filter
NICMOS snapshot search for companions to stars within 10 pc. With a 10 sigma
detection limit of M_J ~ 20 at 10 pc, we can detect companions between 10
and
100 AU that are at least 9 mag fainter than the empirical end of the main
sequence and at least 6.5 mag fainter than the brown dwarf Gl 229B. When
completed, our search will be the largest, most sensitive, volume-limited
search
for VLM companions ever undertaken. Our four-filter search will permit
unambiguous identification of VLM-companion candidates for follow-up
observation. Together with IR speckle and deep imaging surveys, our program
will
firmly establish the LF for VLM companions at separations of 1-1000 AU and
the
multiplicity fraction of all stars within 10 pc.

STIS 9505

The Evolution of Molecular Clouds.

The combined STIS, FUSE and ground-based results will yield information
needed
to understand the role of ablation in the evolution of the central clouds.

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

STIS 9606

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

STIS 9608

CCD Bias Monitor – Part 2

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 9673

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

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.

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

HSTAR 8974: GSacq(3,2,3) results to Finelock Backup (3,0,3) at AOS. The
GSACQ(3,2,3) of 084/17:05:31 – 17:12:58 which begun
during ZOE resulted
to fine lock backup (3,0,3), at AOS 084/17:27:36
using FGS#3. There were
no indication flag(s) at AOS. Unable to determine
FGS Modes and Flag Bit
Changes, pending ETR Dump at 084/23:10:30. Possible
observations affected:
WFPCII 50,51 STIS 50, ACS 69. The guide star
acquisition for this observation
was non-nominal, further analysis will determine if a
repeat observation is
required.

HSTAR 8975: ReAcq(3,2,3) Requires 2 attempts to gain FL on FGS2. OTA SE,
investigating
PTAS log files, uncovers ReAcq that required 2
attempts to achieve FL Data
Valid on FGS2. The preceding GSAcq @ 081/18:29:32
succeeded on first attempt.
Under investigation.

OPS NOTES EXECUTED: 1091-1 – Adjust ACS Error Count Limit @ 084/2233z

                          SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq              10                        10
FGS REacq               5                          5
FHST Update            19                        19
LOSS of LOCK

SIGNIFICANT EVENTS: None