Status Report

HST Daily Report # 3266

By SpaceRef Editor
December 18, 2002
Filed under , ,






NICMOS Post-SAA calibration – CR Persistence Part 1.

A new procedure proposed to alleviate the CR-persistence problem of NICMOS.
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
darks will be non-standard reference files available to users with a USEAFTER
date/time mark.


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.


Cosmological Parameters from Type Ia Supernovae at High Redshift.

{SNe Ia} that will be of long lasting value as a record of the expansion
of the universe.

WFPC2 9341

Saturn’s Rings and Small Moons

We propose to continue our long-term survey of Saturn’s rings, using the unique
capabilities of the WFPC2, to obtain a coherent set of high resolution,
multi-color images of the Saturnian ring system over the full range of ring
and phase angles accessible from the Earth over the course of 1/4 Saturn
year {7
Earth years}. Our Cycle 6 {program 6806} and long-term Cycle 7 {7427} and Cycle
8 {8398} observations explored the rings from their nearly edge-on aspect, just
after the most recent ring plane crossings, to their current moderate
inclination. Here, we propose to complete our survey during the next three
Saturn oppositions {Cycles 9–11}, as the rings gradually approach their most
open configuration, shortly before the arrival of the Cassini spacecraft at
Saturn. Our key goals are to investigate the composition, structure, and
particle properties of the rings from variations of ring brightness and color
with radius, tilt and phase angle, to measure the azimuthal asymmetry of the A
ring and the temporal variability of the clumpy F ring, to follow the enigmatic
behavior of the renegade satellites Prometheus and Pandora, and to observe the
south polar region of Saturn.

ACS/HRC 9379

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

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.

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
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 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

GO 9493

Revealing the nature of low luminosity radio-galaxies with imaging polarimetry

HST imaging of low luminosity FR I radio-galaxies allowed us to isolate for the
first time their optical nuclear emission from that of the host galaxy. Fluxes
of these unresolved nuclear sources strongly correlate with those of the radio-
cores, suggesting a common non-thermal origin. The picture which emerges is
these radio-galaxies differ in many fundamental aspects from the other classes
of AGN as they might be lacking the substantial BLR, thermal disk emission and
torii, usually associated to active nuclei, probably reflecting a fundamentally
different accretion mode. On the other hand, these results support the
identification of FR I as the misoriented population of BL Lac objects. It is
crucial at this stage to firmly establish the synchrotron origin of these
nuclear sources. A simple and direct test can be performed by measuring their
polarization. In case of synchrotron emission we expect to detect significant
nuclear polarization, as routinely measured in BL Lac objects, at level of 3 –
20 We thus propose to obtain imaging polarimetry of a sample formed by the 9
nearest FR I radio- galaxies.

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 9593


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

CAL/WF2 9597

Intflat Sweep, Visflat Sweep, and Filter Anomaly Check

STIS 9605

CCD Dark Monitor-Part 1

STIS 9607

CCD Bias Monitor – Part 1

high-S/N superbiases and track the evolution of hot columns.

ACS 9647

CCD Daily Monitor Part I

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 9692

STIS Pure Parallel Imaging Program: Cycle 10

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

ACS 9694

HST Imaging Polarimetry of the Light Echo around V838 Monocerotis. Part III.

V838 Mon, which burst upon the astronomical scene in January 2002, is a
completely unanticipated new kind of object: it has undergone an outburst
somewhat similar to that of an extremely slow nova, but its spectrum is unique
and totally unlike that of any type of nova. Knowledge of the distance and
luminosity of this unexpected object is crucial to understanding its nature and
origin. A rapidly evolving light echo around V838 Mon was detected from the
ground by Henden in February, and provides us with the means to make a direct
geometric determination of the distance through polarimetric imaging. We
submitted a DD proposal to obtain polarimetry of the light echo with ACS, and
the program was approved for 2 orbits {GO/DD-9587}. Our first one-orbit visit,
on 2002 April 30, provided spectacular $B$-band images of the light echo, with
at least 11 distinct rings {corresponding to sheets of interstellar material in
the line of sight, and/or structures in circumstellar material}. On the
basis of
this initial image, we submitted a second DD proposal {“Part~II”}, which was
approved for one additional orbit {GO/DD-9588}. Our 2nd, two-orbit visit was on
2002 May 20, and consisted of polarimetric imaging in $B$ and $V$, and direct
imaging in $I$. These results were even more spectacular, and will be the basis
for a forthcoming press release. The purpose of this supplemental request
{“Part~III”} is to ask for four more visits between now and the beginning of
Cycle~12, for a total of 15 additional orbits. The urgency for obtaining the
observations now arises from the expected fast decay of the surface brightness,
which goes as $t^{-1}$ for the “superluminal” material well away from the
star, and as $t^{-2}$ for circumstellar material. In addition to the distance
determination, our observations will provide a 3-D map of the interstellar {or
circumstellar} medium in the vicinity of V838~Mon. The approved program is
for 2
visits, for a total of 9 orbits.


NICMOS Parallel Thermal Background

NICMOS Camera 2 pure parallel exposures in the F222M and F237M filters to
establish the stability of the HST+NCS+Instrument thermal emission. This data
will be compared against the already available Camera 3 measurements in F222M
which show an increased thermal background.


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

HSTAR 8882: GS Acquisition (1,2,1) @ 352/02:16:20Z failed to gyros only
due to
SRLE on FGS 1 and 2. U2,3FM @ 352/02:10:07Z showed
errors of -134.986,
-9.467, -101.232 and errors of -5.520, -8.680,
-5.612. FHST Map
@ 352/02:23:53Z showed errors of -17.679, -8.381,
Vehicle was in SAA 1 during anomaly. Following GS
Acquisition @ 352/03:18:42Z
was successful. Under investigation.



                         SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq              7                         6              See Hstar # 
REacq              9                          9 

FHST Update 17 17 LOSS of LOCK


FOT received SMS SA350M02_F1 TOO intercept products @ 351/22:40Z, processed,
signed off, and transferred loads to all CCS strings @ 352/00:35Z. Uplinked
NSSC-1 load @ 352/03:40Z.

SpaceRef staff editor.