Status Report

NASA Hubble Space Telescope Daily Report # 3401

By SpaceRef Editor
July 11, 2003
Filed under , ,

DAILY REPORT # 3401

PERIOD COVERED: DOY 190

OBSERVATIONS SCHEDULED

ACS 9401

The ACS Virgo Cluster Survey

We propose the most comprehensive imaging survey to date of low-redshift,
early-type galaxies. Our goal is to exploit the exceptional imaging
capabilities
of the ACS by acquiring deep images — in the SDSS g^ and z^ bandpasses
— for
163 E, S0, dE, dE, N and dS0 galaxies in Virgo, the nearest rich cluster.
This
extraordinary dataset would likely constitute one of the principal legacies
of
HST, and would have widespread applications for many diverse areas of
astrophysics. Our immediate scientific objectives are threefold: {1} measure
metallicities, ages and radii for the many thousands of globular clusters
{GCs}
in these galaxies, and use this information to derive the protogalactic mass
spectrum of each galaxy; {2} measure the central luminosity and color
profile of
each galaxy, and use this information to carry out a completely independent
test
of the merging hierarchy inferred from the GCs, with the aid of N-body codes
that simulate the merger of galaxies containing massive black holes; and {3}
calibrate the z^ -band SBF method, measure Virgo’s 3-D structure, and carry
out
the definitive study of the GC luminosity function’s precision as a standard
candle. Our proposed Virgo Cluster Survey will yield a database of
unprecedented
depth, precision and uniformity, and will enable us to study the record of
galaxy and cluster formation in a level of detail which will never be
possible
with more distant systems.

STIS 9418

The Sight-line toward PHL 1811: A Rare Chance to Probe a Lyman Limit System
at
Very Low

The sight-line to an extraordinarily bright quasar, PHL 1811, penetrates
four
gas systems at z{abs} < z{em} = 0.192. One of them is a Lyman limit system
{LLS:
N{H I} > 10^17.5 cm^-2} at z{abs} = 0.08088 which is especially well suited
for
a study of atomic abundances, local density, and ionization state. We
propose to
obtain a STIS E140M spectrum with moderately good S/N so that we can measure
absorption features that will permit the determinations of overall
metallicity
of the system, its nucleosynthetic ratios Alpha/Fe and Alpha/N, the
fractions
and kinematics of ionized gas, and the amount of gas-phase element
depletions
caused by dust. The LLS should be close enough for us to identify an
associated
galaxy, but to be sure we do not miss one very close to the quasar in
projection, we plan to supplement our spectrum with a short- exposure ACS
HRC
image of the quasar’s immediate surroundings.

ACS 9468

ACS Grism Parallel Survey of Emission- line Galaxies at Redshift z pl 7

We propose an ACS grism parallel survey to search for emission-line galaxies
toward 50 random lines of sight over the redshift interval 0 < z pl 7. We
request ACS parallel observations of duration more than one orbit at high
galactic latitude to identify ~ 300 HAlpha emission-line galaxies at 0.2 pl
z pl
0.5, ~ 720 O IILambda3727 emission-line galaxies at 0.3 pl z pl 1.68, and
pg
1000 Ly-alpha emission-line galaxies at 3 pl z pl 7 with total emission line
flux f pg 2* 10^-17 ergs s^-1 cm^-2 over 578 arcmin^2. We will obtain direct
images with the F814W and F606W filters and dispersed images with the
WFC/G800L
grism at each position. The direct images will serve to provide a zeroth
order
model both for wavelength calibration of the extracted 1D spectra and for
determining extraction apertures of the corresponding dispersed images. The
primary scientific objectives are as follows: {1} We will establish a
uniform
sample of HAlpha and O II emission-line galaxies at z<1.7 in order to obtain
accurate measurements of co-moving star formation rate density versus
redshift
over this redshift range. {2} We will study the spatial and statistical
distribution of star formation rate intensity in individual galaxies using
the
spatially resolved emission-line morphology in the grism images. And {3} we
will
study high-redshift universe using Ly-alpha emitting galaxies identified at
z
pl 7 in the survey. The data will be available to the community immediately
as
they are obtained.

STIS/MA2/ACS/HRC 9501

Life Cycles of Radio Galaxies

Now, for the first time, we can probe the duration of nuclear activity and
its
duty cycle and the relationship between the growth of the bulge {via a
starburst} and the growth of the BH {via fueling the AGN}. We have
identified a
class of powerful radio galaxy which displays both an outer `older’ radio
source
as well as an inner `younger’ radio source. These `double- doubles’ are
sources
in which the current radio source is propagating outwards through the relic
of
the previous epoch of activity. In 3C 236 we found that repeated episodes of
star formation and radio ejection were indeed temporally linked. We propose
to
obtain images of the host galaxies of 4 additional double-double radio
galaxies
in the NUV with STIS and the R band with ACS/HRC. The proposed HST
observations
will allow us to determine the existence of young star forming regions in
these
double-double sources. Follow up imaging and spectroscopy combined with our
detailed radio imaging, will allow us to use the double-doubles to address
critical questions concerning probe the relationship between star formation
and
AGN fueling, e.g., – Over what time scales do these processes occur ? — are
they short and intense or long and gradual ?

WFPC2 9595

WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt3/3

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.

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.

ACS 9674

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.

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
history
of the early solar system, the internal structure of distant ice-rock
bodies,
and even the genesis of the Pluto-Charon binary. Within the past 18 months,
9
KBO satellite systems have been discovered, allowing for the first time the
possibility of characterizing a sample of KBO satellite orbital properties.
We
propose HRC observations to determine satellite orbits in the 6 best cases.
We
have carefully devised a strategy for each of these 6 systems to make
maximum
use of ground-based observations, previous HST observations, and the
smallest
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.
Our
strategy relies heavily on extensive Monte Carlo simulations to define
optimal
times of observing such that each new point obtained gives maximum leverage
for
refining the orbital solution. We find that with this strategy we can
provide
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
scientific
output with optimal use of scarce resources.

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.

ACS/HRC 9805

OGLE-TR-56b: The Most Interesting Transiting Planet

Our team has recently succeeded in confirming spectroscopically the
discovery of
the first extrasolar giant planet found in a transit search: OGLE-TR-56b.
Its
main parameters are: mass = 0.9 Jupiters, size = 1.3 Jupiters. Thus,
OGLE-TR-56b
appears to be similar to HD 209458b, the only other known transiting giant
planet. Unfortunately, our planet radius determination is uncertain due to
the
very limited precision of the ground-based photometry, and does not allow
for a
meaningful comparison with theoretical model predictions. We propose HST
observations with the ACS-HRC of the main transit of OGLE-TR-56b, which will
improve the precision and the accuracy of the planet parameters by close to
a
factor of 10. In addition, we propose a timing experiment for the planet’s
extremely close orbit {1.2-day period, 0.023 AU from the star}, which will
allow
us to detect the orbital decay and test convection theories.

ACS/WFC/HRC 9895

The Role of Groups in the Evolution of Galaxies at Intermediate Redshifts

Groups are the most common environment experienced by galaxies, yet they
remain
the least studied. The tidal fields and dynamical friction encountered by
galaxies in groups probably holds the key to understanding the role of
environment in driving the evolution of galaxies since z ~ 1. To study the
evolution of galaxies in the group environment, we propose the first
unbiased
HST study of groups at moderate redshifts. Unlike previous HST group
samples,
that relied on radio or X-ray properties, our kinematically selected sample
is
drawn from a large redshift survey and is not biased towards unusually dense
groups. HST imaging is essential to determine the morphology of galaxies in
these systems and contrast this with the properties of galaxies in denser
and
more evolved groups and rich clusters at these epochs. HST data are also
required to adequately compare the properties of groups at intermediate
redshifts with local group samples derived from the 2df and Sloan surveys.
We
will combine the HST images with deep ground-based observations to study how
morphologies and stellar populations of galaxies in groups have evolved in
time.
These observations are key to understanding the decline in the volume
averaged
star formation rate in the universe.

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 ideal.

FLIGHT OPERATIONS SUMMARY:

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

COMPLETED OPS REQs:

  • 17000-1 – Initial Activation of OCA @ 190/1242z

OPS NOTES EXECUTED:

  • 1129-0 – Set Limit for CCC 5 K1 V/T Level 2 @ 190/1330z
  • 1131-0 – Increase Battery 3 upper temperature limit by 0.5 degrees @
  • 190/1621z
  • 1132-0 – HST486 FSW S/W Memory Dump @ 190/2207z

                          SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq              13                       13
FGS REacq               2                         2
FHST Update            23                       23
LOSS of LOCK

SIGNIFICANT EVENTS:

Successfully activated the EPS Over Charge Avoidance (OCA) Routine on Day
190
(OR 17000-1 with attached script). Commanding to configure the HST486 FSW
and
CCC 5 hardware for the activation was completed @ 190/12:41:38Z. EPS and
FSW
SEs verified the nominal operations of OCA and TRSWCC/VTFE for the first
orbit
following the installation. No K-relay cycling occurred, OCA opened
relays, as
expected, for the batteries that reached cut-off during Full Charge period
in
orbit day, transition to Trickle Charge was executed nominally in orbit day
by
FSW, and Trickle Charge exit occurred nominally in orbit night @ 190/14:08Z.

Successfully completed (after slow start) SM-4 Aft Flight Deck Internal
Command
Test 190/11:59Z -19:00Z. Verified HITT test procedures and SOC scenario
file changes
that were discovered during earlier testing. Also, verified several
additional CCS
mnemonics that were added during the same analysis period.

HST SM-4 Aft Flight Deck Internal Command testing scheduled 191/11:00Z –
21:00Z with GDOC,
SOC, HITT, and CCS using CCS "C" String with CCS Release 4.0.2.2 and PRD
S07200. The purpose
of this testing is to dry run SM-4 telemetry through the PSS to create
scenario files and
to verify procedures.

SpaceRef staff editor.