Status Report

NASA Hubble Space Telescope Daily Report # 3427

By SpaceRef Editor
August 17, 2003
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WFPC2 9595


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

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.

STIS 9615

Cycle 11 MAMA Dark Monitor

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

STIS 9633

STIS parallel archive proposal – Nearby Galaxies – Imaging and

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.

ACS 9650

CCD Hot Pixel Annealing

Hot pixel annealing will be performed once every 4 weeks. The CCD TECs
will be turned off and heaters will be activated to bring the WFC
detector temperature to about +10C. The HRC temperature will reach
about 30C.This state will be held for approximately 24 hours, after
which the heaters are turned off, the TECs turned on, and the CCDs
returned to normal operating condition. To assess the effectiveness of
this procedure, a bias and two dark images will be taken before and
after the annealing procedure for both WFC and HRC.

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.

STIS 9708

STIS Pure Parallel Imaging Program: Cycle 11

This is the default archival pure parallel program for STIS during
cycle 11.

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.

WFPC2 9710

POMS Test Proposal: WFII backup parallel archive proposal

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

STIS 9718

SMC Extinction Curve Towards a Quiescent Molecular Cloud

The lack of 2175 A bump in the SMC extinction curve is interpreted as
an absence of small carbon grains. ISO mid-IR observations support
this interpretation by showing that PAH features are absent in the
spectra of SMC and LMC massive star forming regions. However, the only
ISO observation of an SMC quiescent molecular cloud shows all PAH
features, indicating a PAH abundance relative to large dust grains
similar to that of Milky Way clouds. We identified a reddened B2III
star associated with this cloud. We propose to observe it with STIS to
derive the xetinction curve of SMC dust away from HII regions. This
observation will provide the first measure of the extinction
properties of SMC dust away from star forming regions. It will allow
us to disentangle the effects of metallicity and star formation on the
SMC extinction curve and dust composition and to assess the relevance
of the SMC bump-free extinction curve to low metallicity and/or
starburst galaxies in general.

STIS 9730

UV Spectroscopy of the Hot, Helium-Core White Dwarf Companion in HR 1608

We propose to observe the FUV spectrum of the hot, helium-core white
dwarf in the binary system HR 1608 in order to determine if there are
suitable spectral lines to obtain a radial velocity orbit for the
white dwarf star. The primary star in this system, with spectral type
K0 IV, dominates the spectrum at visual wavelengths. At a temperature
of around 25, 000 K, however, the white dwarf outshines the primary in
the UV. The orbital motion of the primary star has been monitored for
seven years with the CfA Digital Speedometer at Oak Ridge Observatory
in Harvard, MA. In addition, the Hipparcos team noted excess scatter
in the astrometric solution which, though unexplained at the time, we
now know to be due to the orbital motion. Combining the astrometric
and spectroscopic data, we have solved for the orbital elements,
including the inclination of the system. In order to obtain a
dynamical mass for the star, the orbital motion of both stars must be
observed, thus the need for monitoring the white dwarf in the UV. As
the first step in this endeavor, we propose to obtain a STIS spectrum
of the white dwarf star to discover if there are spectral lines with
which its radial velocity could be measured precisely enough to
calculate a dynamical mass.

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 spatial variation of the CIII] 1909 Angstrom emission
lines across the nebulae. Much of our current knowledge of carbon
abundances in planetary nebulae and HII regions are based on UV
spectroscopic observations of this line yet there have not been any
studies of its spatial variations in nebulae compared to several of
the prominent optical lines {e.g. [OIII] 5007 Angstroms}. Such
observations, coupled 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 study
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.

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.


Where is the Local Hot Gas?

We wish to sample the absorption characteristics of 3 lines-of-sight
in the local interstellar medium to establish the physical location of
the production sites of the highly ionized absorption lines of CIV,
SiIV and NV. Such lines are formed at gas temperatures of ~ 100, 000K
and all have been widely observed throughout the Galaxy. However,
evidence for the formation of any of these high ions within the hot
gas of the Local Bubble {LB} remains inconclusive, supporting the
similar lack of detections of the OVI ion {T ~ 300, 000K} within 100pc
recently reported by the FUSE satellite. Using our recently gained
information on the contours of the neutral boundary to the LB, we have
selected 3 pairs of stars located just within, and just beyond the LB
boundary. We shall test whether high ionization ions are formed either
{a} beyond the LB boundary in more distant interstellar bubbles of hot
gas, {b} at the conductive interface of the LB neutral boundary, or
{c} at possible conductive interfaces between hot gas within the LB
and the diffuse clouds embedded within it. Hopefully, these
observations will enable theorists to better model the {anomalous}
ionization state, pressure and chemical abundance of the local
interstellar gas and will assist in the interpretation of data soon to
be gained from the NASA CHIPS mission.

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/WFC 9902

The Evolution of the Host Galaxies of Radio-Quiet Quasars

Study of the host galaxies and environments of high redshift AGN is
proving a valuable probe of current theories of how galaxies form and
evolve. Results from our NICMOS imaging program have indicated that
the hosts of z ~ 2 — 3 faint radio-quiet quasars {RQQ} have
luminosities only around local L*, making them similar to Lyman-break
field galaxies at the same redshifts, and to the low-z hosts RQQ
hosts. This is roughly consistent with theoretical predictions of
Kauffmann & Haehnelt {2000} for the hierarchical buildup of galaxy
hosts and their relation to their resident supermassive black holes.
The luminosity of the AGN in these RQQ is key to understanding this
relationship, however, and we are making a comprehensive archival HST
imaging study of the hosts of RQQs from low to high z at a range of
nuclear luminosities. At intermediate z, however, there are no studies
of the hosts of RQQs in the faint luminosity range that represents the
bulk of the quasar population. In the present proposal, we request
imaging at the same rest-wavelengths as our high-z sample of the hosts
of 10 similarly luminous RQQs at z ~ 0.9. These data will fill in an
important part of the parameter space defined by quasar luminosity and
redshift. Combined with existing HST data they will allow us to trace
the evolution of the hosts of RQQ and that of the relationship between
quasar luminosity and host galaxy luminosity.


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 indispensible 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.

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 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


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

HSTAR 9110 – GSacq(3,1,3) at 226/07:58:35 to 08:06:12 failed to gyro
control due to Search Ra FGS3 and FGS1 after
multiple attempts. Map at 08:06:26 showed errors of
-7.321,-7.292 and -11.036. The 226/09:09:02 also failed to
RGA only. Possible observations 110 – 115. The guide
star acquisition for this observation non-nominal, further
analysis will determine if a repeat observation is required.

HSTAR 9111 – The GSAcq(1,2,1) of 226/19:22:59 – 19:30:24, which begun
during ZOE period resulted to (1,0,1) using FGS1
at AOS. There were no indication Modes and Flag bit
changes) available pending ETR Dump. The following REacq at 20:59:10
also resulted in FLBU on FGS#1. Prior FM Updates at
226/19:16, 19:19 showed go Possible Observations
affected: ACS 131 thru STIS 123,124 WFPC 83 thru 85. The guide
star acquisition for this observation non-nominal,
further analysis will determine if a repeat observation

17027-1 Setup NICMOS Memory Monitor in prep for FW test @226/2212z


                         SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq             10                       9               
(HSTAR 9110)
FGS REacq             4                         3               
(HSTAR 9110)
FHST Update           29                       29


SpaceRef staff editor.