NASA Hubble Space Telescope Daily Report # 3586
HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science
DAILY REPORT # 3586
PERIOD COVERED: DOY 97
OBSERVATIONS SCHEDULED
ACS/HRC/WFC 10060
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.
ACS/HRC/WFC 9884
Dwarf Elliptical Galaxies in Nearby Groups: Stellar Populations and
Abundances
The M81 group is of the nearest galaxy groups, but its properties are quite
different from the Local Group, providing a different evolutionary
environment
for its member galaxies. This team has been studying M81-group analogs to
Local
Group dwarf elliptical {dE} galaxies. We observed two M81-group dEs with
WFPC2:
the results were published in Caldwell et al. {1998}. These observations
revealed the upper two magnitudes of the red giant branch, yielding
distance via
the luminosity of the red giant branch tip, mean abundance via the mean
giant
branch color and first assessment of the star formation history via the
frequency of occurrence of upper-AGB stars. Despite the different
environment,
the two M81-group dEs follow the Local Group {absolute magnitude, mean
abundance} relation. But without data for additional dEs in nearby groups,
particularly at higher luminosities, we can’t definitely say whether this
relation is universal or not. Establishing the answer to this question is
vital
because the relation is fundamental to theories of dE formation within dark
matter halos, and the general applicability of these theories requires
demonstration that the relation isn’t strongly influenced by environment.
This
proposal requests ACS/WFC observations of five M81-group dEs to resolve this
question.
ACS/WFC 9717
Low Redshift Cluster Gravitational Lensing Survey
This proposal has two main scientific goals: to determine the dark matter
distribution of massive galaxy clusters, and to observe the high redshift
universe using these clusters as powerful cosmic telescopes. Deep, g, r, i,
z
imaging of a sample of low-z {0.2-0.4} clusters will yield a large sample of
lensed background galaxies with reliable photometric redshifts. By combining
strong and weak lensing constraints with the photometric redshift
information it
will be possible to precisely measure the cluster dark matter distribution
with
an unprecedented combination of high spatial resolution and area coverage,
avoiding many of the uncertainties which plague ground-based studies and
yielding definitive answers about the structure of massive dark matter
haloes.
In addition, the cosmological parameters can be constrained in a largely
model
independent way using the multiply lensed objects due to the dependence of
the
Einsteinng radius on the distance to the source. We can also expect to
detect
several highly magnified dropout galaxies behind the clusters in the
redshift
ranges 4-5 5-6 and 7-8, corresponding to a drop in the flux in the g, r, and
i
bands relative to longer wavelength. We will obtain the best information to
date
on the giant arcs already known in these clusters, making possible detailed,
pixel-by-pixel studies of their star formation rate, dust distribution and
structural components, including spiral arms, out to a redshift of around
z~2.5
in several passbands.
ACS/WFC/HRC 9771
The local Hubble flow and the density field within 6 Mpc
Great progress has been made recently in accurate distance measurements of
nearby galaxies beyond the Local Group based on the luminosity of the tip
of the
red giant branch {TRGB}. Over the last three years, snapshot surveys with
HST
have provided us with the TRGB distances for more than a hundred nearby
galaxies
obtained with an accuracy of about 10%. The local velocity field within 5
Mpc
exhibits a significant anisotropy which disagrees with a spherical
Virgo-centric
flow. The local Hubble flow is very cold, with 1-D rms deviations of ~30
km/s.
Cosmological simulations with Cold Dark Matter can only realize such low
dispersions with a combination of a low mean density of matter and a
substantial
component with negative pressure. There may be a constraint on the equation
of
state w=-p/rho. Our observations will concentrate on 116 galaxies whose
expected
distances lie within 4 – 6 Mpc, allowing us to trace a Dark Matter
distribution
in the Local Volume with twice the information currently available. The
program
is a good one for SNAP mode because the order and rate that the
observations are
made are not very important, as long as there is good completion over
several
years.
ACS/WFC/WFPC2 9822
The COSMOS 2-Degree ACS Survey
We will undertake a 2 square degree imaging survey {Cosmic Evolution
Survey —
COSMOS} with ACS in the I {F814W} band of the VIMOS equatorial field. This
wide
field survey is essential to understand the interplay between Large Scale
Structure {LSS} evolution and the formation of galaxies, dark matter and
AGNs
and is the one region of parameter space completely unexplored at present by
HST. The equatorial field was selected for its accessibility to all
ground-based
telescopes and low IR background and because it will eventually contain
~100,
000 galaxy spectra from the VLT-VIMOS instrument. The imaging will detect
over 2
million objects with I> 27 mag {AB, 10 sigma}, over 35, 000 Lyman Break
Galaxies
{LBGs} and extremely red galaxies out to z ~ 5. COSMOS is the only HST
project
specifically designed to probe the formation and evolution of structures
ranging
from galaxies up to Coma-size clusters in the epoch of peak galaxy, AGN,
star
and cluster formation {z ~0.5 to 3}. The size of the largest structures
necessitate the 2 degree field. Our team is committed to the assembly of
several
public ancillary datasets including the optical spectra, deep XMM and VLA
imaging, ground-based optical/IR imaging, UV imaging from GALEX and IR data
from
SIRTF. Combining the full-spectrum multiwavelength imaging and spectroscopic
coverage with ACS sub-kpc resolution, COSMOS will be Hubble’s ultimate
legacy
for understanding the evolution of both the visible and dark universe.
STIS/CCD 10018
CCD Dark Monitor-Part 2
Monitor the darks for the STIS CCD.
STIS/CCD 10020
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/CCD/MA1 9874
Probing IGM Phases, Metals, and the Cosmic Web with New SDSS QSOs
We propose STIS G140L SNAPSHOT observations of 100 new z < 1 QSOs from the
Sloan
Digital Sky Survey for studies of the IGM. These targets will be chosen to
simultaneously maximize IGM pathlength and to form closely spaced groups of
2-8
QSO sightlines within 1 h^-1 Mpc of a foreground galaxy. These observations
will, in the long term, provide a rich database of target QSOs for detailed
study by COS of the IGM phases, metallicity, and relationship to the large
scale
structure. In the near term, these observations will detect up to 10 Lyman
alpha
clouds with N_HI > 10^14 and 3 clouds with N_HI > 10^15, per target. Thus
they
will provide an immediate test of filamentary structure in the "cosmic web"
within 1 h^-1 Mpc of galaxies. We ask for 22 minute exposures for each
target
with STIS/G140L to obtain S/N = 5-16 for these V = 16 – 18 QSOs. These
observations will be sensitive to Lyman alpha equivalent widths ranging
from 300
mA for the brighter sources to 600 mA at the fainter end. These targets
represent a Deltaz pathlength of 17 {at 50% yield}, with Deltaz = 10 in the
range where Lya, Lyb, and O VI lie in the HST band. These observations will
also
refine predictions of the FUV flux of QSOs based on the larger SDSS sample
and
will estimate the degree to which such factors as intrinsic and Galactic
extinction, variability, and intervening absorption can be controlled. If
successful, this technique could make UV-prequalification SNAPs of QSOs
obsolete, at a significant savings of HST time. Our observations lie at the
median duration for SNAPs, and in the range most likely to be executed. Our
program accomplishes both near- and long-term goals at a relatively low
investment of time, and thus is ideally suited for a SNAP proposal. To
ensure
maximum scientific return for our own purposes and for additional science
{HVCs,
Galactic halo} we waive the right to a proprietary data period.
WFPC2 10067
WFPC2 Cycle 12 Decontaminations and Associated Observations
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 10070
WFPC2 CYCLE 12 Supplemental Darks Part 2/3
This dark calibration program obtains 3 dark frames every day to provide
data
for monitoring and characterizing the evolution of hot pixels.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports of
potential non-nominal performance that will be investigated.) None
COMPLETED OPS REQs:
17119-0 TDRS 171 Test Event @ 097/16:41z
17120-0 ACS and STIS EEPROM memory dumps @ 097/21:59z
OPS NOTES EXECUTED: NONE
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 08 08
FGS REacq 04 04
FHST Update 18 18
LOSS of LOCK
SIGNIFICANT EVENTS:
Continue NICMOS Proposal 10097, adjust NCS setpoint temperature
by -0.5 K @ 098/11:58Z via SMS.
Set-up and Execution of HST FSW 2.5b On-orbit Functional, Ops
Acceptance Test scheduled 098/10:00Z – 099/04:00Z with GDOC, HITT,
SE, and VEST using CCS "D" String (prime) with CCS Release 5.0.3.1
and PRD O06400ST and CCS "C" String (secondary) with CCS Release 4.0.3.1
and PRD O06400T. The purpose of this testing is to verify the new
functionality of FSW 2.5b with PRD O6400 in an operational scenario.
