NASA Hubble Space Telescope Daily Report # 3544
HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science
DAILY REPORT # 3544
PERIOD COVERED: DOY 34
OBSERVATIONS SCHEDULED
ACS 9438
The Origin of the Intergalactic Globular Cluster Population in Abell
1185
We request deep V and I observations with ACS to examine the properties
of a
newly discovered population of intergalactic globular clusters in the
core of
the rich galaxy cluster Abell 1185. Our previous WFPC2 observations of
this
field {GO-8164} revealed an excess of five times the number of objects
at the
expected magnitudes of globular clusters compared to the Hubble Deep
Fields. The
colors and luminosity function of these intergalactic globular clusters
will
place strong constraints on their origin, which in turn will yield new
insights
to the evolution of galaxy populations in dense environments
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.
ACS/HRC/WFC 10059
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/STIS/CCD 9836
The role of dark matter and intracluster gas in galaxy formation and
cluster
evolution
We propose a fully-sampled mosaic of 41 ACS images to survey galaxy
morphologies
and measure weak lensing signals to the turn-around radius in the X-ray
luminous
cluster, MS0451-03 {z=0.54}. The aim is to isolate the physical
processes which
affect the evolution of cluster galaxy morphologies in the context of
well-defined dynamical system. The study will be used in contrast to a
successful campaign undertaken in Cycle 9 on a optically-selected
target. By
comparing morphologies with spectroscopic and Chandra X-ray data, we
will
quantify the role of the intracluster medium and associated
substructures and
establish the timescales and physical regions within which the various
environmental processes occur.
ACS/WFC 10054
ACS photometric Stability
A set of four spectrophotometric standard stars {GD71, G191B2B, GD153,
and
HZ43}
is observed once with ACS’s WFC and HRC through all filters, except the
ramp
filters, to assess the sensitivity of the instrument and measure
accurate
photometric zero points. The stars are placed at the centre of the
aperture, and
two images are taken through each filter. This programme is based on
proposals
9020 and 9654 designed for SMOV and Cycle 11, and also on programme 9563
from
the interim period. No RAMP filters are calibrated here. The exposure
times
have
been calculated to reach, on average, SNR~350 in the central pixel for
broad
band filters.
FGS 9881
Dynamical Masses and Radii of Four White Dwarf Stars
The cool white dwarf stars WD1639+153 and WD1818+126 were recently
resolved by
HST FGS1r to be double degenerate binary systems with projected
separations of
112 mas and 174 mas respectively. At a distance of less than 50 pc they
may
both
have periods shorter than about 20 years, making them ideal candidates
for
follow up studies for dynamical mass determinations. This will increase
the
number of white dwarfs with dynamical mass measurements from the current
4
up to
8. Continued observations of these white dwarfs along with nearby field
stars
with the FGS will accurately determine the orbital elements and parallax
of
each
system. The mass and radius of all four white dwarfs can be determined
to an
unprecedented 1%, making it possible to test and calibrate the
theoretical
white
dwarf mass radius relation at the cool end of the cooling curve for the
DA and
DC subclasses. Since the components of the binary are coeval, once the
mass and
radius, and hence the cooling age of each star is known, it will be
possible to
estimate the relation between the initial mass and final mass for all
four
white
dwarfs. We are requesting a total of 4 HST orbits per year for the next
three
cycles to initiate the process that will result in a determination of
the mass
and radius of the four white dwarfs.
NIC/NIC3 9865
The NICMOS Parallel Observing Program
We propose to continue managing the NICMOS pure parallel program. Based
on our
experience, we are well prepared to make optimal use of the parallel
opportunities. The improved sensitivity and efficiency of our
observations will
substantially increase the number of line-emitting galaxies detected. As
our
previous work has demonstrated, the most frequently detected line is
Halpha at
0.7<z<1.9, which provides an excellent measure of current star formation
rate.
We will also detect star-forming and active galaxies in other redshift
ranges
using other emission lines. The grism observations will produce by far
the best
available Halpha luminosity functions over the crucial–but poorly
observed–redshift range where galaxies appear to have assembled most of
their
stellar mass. This key process of galaxy evolution needs to be studied
with IR
data; we found that observations at shorter wavelengths appear to have
missed a
large fraction of the star-formation in galaxies, due to dust reddening.
We
will
also obtain deep F110W and F160W images, to examine the space densities
and
morphologies of faint red galaxies. In addition to carrying out the
public
parallels, we will make the fully reduced and calibrated images and
spectra
available on-line, with some ground-based data for the deepest parallel
fields
included.
NIC1 9833
T Dwarf Companions: Searching for the Coldest Brown Dwarfs
Faint companions to known stars have historically led to the discovery
of new
classes of stellar and substellar objects. Because these discoveries are
typically limited by the flux ratio of the components in the system, the
intrinsically faintest companions are most effectively identified around
the
intrinsically faintest primaries. We propose to use NICMOS to image a
sample of
22 of the coolest known {T-type} brown dwarfs in the Solar Neighborhood
in
order
to search for fainter and cooler brown dwarf companions. The high
spatial
resolution of the NIC 1 detector enables us to distinguish binary
systems with
apparent separations greater than 0"08, or physical separations greater
than 1.2
AU at the nominal distances of the objects in our sample. Furthermore,
the
substantial sensitivity of NICMOS imaging allows us to probe companion
masses of
5-50 Jupiter masses and companion effective temperatures of 250-1300 K
in a
maximally efficient manner. Based on work to date, we expect that
roughly
20% of
the objects in our sample will be binary, and that one or two of these
will
likely harbor a significantly fainter secondary. Hence, we expect to
find a
companion cooler than any currently known brown dwarf, a potential
prototype for
the next spectral class. In addition, our investigation will add
substantially
to the sample of known binary brown dwarfs, allowing improved
statistical
analyses of the binary fraction, separation distribution, and mass ratio
distribution of these systems, key quantities for probing brown dwarf
formation.
We will also identify optimal substellar systems for astrometric mass
measurements, a critical check for theoretical models of brown dwarfs
and
extrasolar planets.
NIC1/NIC2/NIC3 9997
Photometric Recalibration
This proposal extends the NICMOS photometric calibration for the NCS era
to
cover four standard stars: G191B2B, P330E, P177D, and GD71.
NIC3 9735
ACS, NICMOS, and STIS Observations of Three Ongoing Mergers
We propose to make ACS {U, B, V, I, H alpha}, NICMOS {J, H, K}, and STIS
{long-slit H alpha} observations of NGC 520, NGC 2623, and NGC 3256,
three
merging galaxies in the middle of the Toomre Sequence and currently in
the
throes of violent relaxation. Two of these {NGC 2623 and NGC 3256} are
the most
IR luminous galaxies in the sequence. Hence, these ongoing mergers are
ideal
candidates for studying the triggering mechanism responsible for the
formation
of stars and star clusters. The ACS observations will allow us to age
date the
star clusters, and reliably distinguish clusters from stars based on
their
apparent sizes. They will also be used in conjunction with ground-based
measurements of the stellar velocity dispersion to determine dynamical
masses of
the clusters and hence address the question of whether the IMF is
truncated. The
NICMOS observations will allow us to penetrate the dust and answer
several
fundamental questions such as: What fraction of the young clusters are
hidden by
dust? How do these clusters form and evolve? The STIS observations will
allow us
to study the kinematics of the young cluster system and measure the
pressure and
shock properties which may be triggering the formation of the clusters.
A
better
understanding of how mergers form tremendous numbers of clusters and
stars in
the local universe will help shed light on processes that were crucial
during
galaxy assembly in the high-z universe.
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.
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.
STIS/CCD 10017
CCD Dark Monitor-Part 1
Monitor the darks for the STIS CCD.
STIS/CCD 10019
CCD Bias Monitor – Part 1
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 10023
STIS CCD Spectroscopic Flats C12
Obtain CCD flats on the STIS CCD in spectroscopic mode
STIS/CCD 10085
STIS Pure Parallel Imaging Program: Cycle 12
This is the default archival pure parallel program for STIS during cycle
12.
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.
WFPC2 10084
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.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTAR 9308: At AOS (034/14:08:45Z), GS Acquisition (2,1,1) was observed
in FL on FGS 2 only. FGS 1 did not acquire
lock. Further information
following SSR engineering data dump @ 035/01:06Z.
Under
investigation.
HSTAR 9309: During Network Failure Simulation in Building, at a moment
when there
was no (known) reconfiguration activity, CCS "C"
String HSTnet XX (info intentionally
removed) and xx (info intentionally removed), GUI
telemetry data displays went ‘purple’ and an erroneous
message was displayed, indicating a CCS shutdown
was
in progress. After
clicking "OK" to the advisory pop-up message,
both
PCs data display
resumed (telemetry was displayed in normal
‘yellow’). Other HSTnet and
Backbone GUI telemetry displays on CCS "C" String
did NOT show the loss of
display. There were no event messages to explain
the anomaly. This
anomaly has been seen on CCS "D" String during
testing. Under
investigation.
HSTAR 9310: GS Acquisition (1,2,1) @ 034/21:41:37Z resulted in FL
backup
using FGS 1
due to SSLEX on FGS 2. Prior FHST RD Update @
034/21:25Z showed good attitude
error vector. FHST Map @ 034/22:17:17Z showed
error
values of -5.817, -5.034,
and 1.052 arcsec. Under investigation.
HSTAR 9311: GS Acquisition (1,2,1) @ 034/23:25:21Z resulted in FL
backup
using FGS 2 due
to SSLEX on FGS 1. Prior FHST FM Updates @
034/23:09Z and 23:12Z showed good
attitude error vector. No FHST Maps scheduled to
follow the GS acquisition
due to the MEGG outline and TDRS support, a FAD
could not be generated.
Under investigation.
COMPLETED OPS REQs: None
OPS NOTES EXECUTED:
- 1193-0 Dump SSR-3 Event Status Buffer @034/1557z
- 1193-0 Dump SSR-3 Event Status Buffer @034/1647z
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 07 07
FGS REacq 08 08
FHST Update 18 18
LOSS of LOCK
SIGNIFICANT EVENTS:
Network Failure Simulations was conducted 034/20:55Z 035/00:20Z.
Experienced some problems bringing up the Network, causing the Network
to
slow down, problems were resolved approximately 035/00:20Z, still some
open
issues to work.
