NASA Hubble Space Telescope Daily Report # 3548
HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science
DAILY REPORT # 3548
PERIOD COVERED: DOY 40
OBSERVATIONS SCHEDULED
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 10001
Locating Ultraluminous X-Ray Sources
We propose to observe ultraluminous X-ray sources which are located
near objects bright both in the X-rays and the optical using Chandra
and HST. The presence of these reference objects will allow us to tie
the x-ray and optical references frames and achieve 0.1-0.2 arcsecond
relative position accuracy in searching for optical counterparts to
the ultraluminous x-ray sources. This will be a significant
improvement over the accuracy previously obtained for most ULXs
{limited by Chandra’s absolute astrometry} and will should permit
identification of individual counterparts.
ACS/HRC/WFC 10044
ACS internal CTE monitor
The charge transfer efficiency {CTE} of the ACS CCD detectors will
decline as damage due to on-orbit radiation exposure accumulates. This
degradation will be closely monitored at regular intervals, because it
is likely to determine the useful lifetime of the CCDs. All the data
for this program is acquired using internal targets {lamps} only, so
all of the exposures should be taken during Earth occultation time
{but not during SAA passages}. This program emulates the ACS
pre-flight ground calibration and post-launch SMOV testing {program
8948}, so that results from each epoch can be directly compared.
Extended Pixel Edge Response {EPER} and First Pixel Response {FPR}
data will be obtained over a range of signal levels for both the Wide
Field Channel {WFC}, and the High Resolution Channel {HRC}.
ACS/HRC/WFC 10048
Stability of the ACS CCD: Flat fielding, Photometry, Geometry
This program will verify that the low frequency flat fielding, the
photometry, and the geometric distortion are stable in time and across
the field of view of the CCD detectors. A moderately crowded stellar
field, located ~6′ West of the center of the cluster 47 Tuc, is
observed every three months with the WFC and HRC using the full suite
of broad and narrow band filters. The same field has been observed
during SMOV to derive low frequency corrections to the ground flats
and to create a master catalogue of positions and magnitudes from
dithered observations of the cluster. In Cycle 11, this field was
observed again using single pointings at various roll angles. The
positions and magnitudes of objects are used to monitor local and
large scale variations in the plate scale and the sensitivity of the
detectors. The Cycle 12 program will continue to monitor these effects
and will derive an independent measure of the detector CTE.
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 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 9788
A Narrow-band Snapshot Survey of Nearby Galaxies
We propose to use ACS/WFC to conduct the first comprehensive HST
narrow-band {H-alpha + [N II]} imaging survey of the central regions
of nearby bulge-dominated disk {S0 to Sbc} galaxies. This survey will
cover, at high angular resolution extending over a large field, an
unprecedented number of galaxies representing many different
environments. It will have important applications for many
astrophysical problems of current interest, and it will be an
invaluable addition to the HST legacy. The observations will be
conducted in snapshot mode, drawing targets from a complete sample of
145 galaxies selected from the Palomar spectroscopic survey of nearby
galaxies. Our group will use the data for two primary applications.
First, we will search for nuclear emission-line disks suitable for
future kinematic measurements with STIS, in order to better constrain
the recently discovered relations between black hole mass and bulge
properties. Preliminary imaging of the type proposed here must be
done, sooner or later, if we are to make progress in this exciting new
field. Second, we will investigate a number of issues related to
extragalactic star formation. Specifically, we will systematically
characterize the properties of H II regions and super star clusters on
all galactic scales, from circumnuclear regions to the large-scale
disk.
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/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.
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 9633
STIS parallel archive proposal – Nearby Galaxies – Imaging and Spectroscopy
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.
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 10085
STIS Pure Parallel Imaging Program: Cycle 12
This is the default archival pure parallel program for STIS during
cycle 12.
STIS/CCD/MA1 9759
Confirmation of New Candidates for the Study of Intergalactic Helium
The reionization of intergalactic helium is believed to take place
between redshift 3 and 4. The study of HeII Lyman-alpha absorption in
four quasars at 2.7<z<3.3 demonstrates the great potential of such an
intergalactic-medium {IGM} probe and suggests that the reionization
epoch is at higher redshifts. Clean quasar sightlines may be found
only from massive pre-selection processes in the optical and UV,
because of random, severe absorption by intervening Lyman-limit
systems. The SDSS has discovered approximately 36000 quasars, and we
propose to verify the UV detectability in 70 top candidates for helium
studies extending to even higher redshift. Our proposed approach has
already proven successful, and additional positive confirmations will
allow follow-up observations, with STIS or COS, to pinpoint the epoch
of reionization of the IGM, and the evolution of its properties near
that period.
STIS/MA1 10034
Cycle 12 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.
WFPC2 10068
WFPC2 CYCLE 12 Standard Darks
This dark calibration program obtains dark frames every week in order
to provide data for the ongoing calibration of the CCD dark current
rate, and to monitor and characterize the evolution of hot pixels.
Over an extended period these data will also provide a monitor of
radiation damage to the CCDs.
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 10072
WFPC2 CYCLE 12 INTERNAL MONITOR
This calibration proposal is the Cycle 12 routine internal monitor for
WFPC2, to be run weekly to monitor the health of the cameras. A
variety of internal exposures are obtained in order to provide a
monitor of the integrity of the CCD camera electronics in both bays
{gain 7 and gain 15}, a test for quantum efficiency in the CCDs, and a
monitor for possible buildup of contaminants on the CCD windows.
WFPC2 10082
POMS Test Proposal: WFII backup parallel archive proposal
This is a POMS test proposal designed to simulate scientific plans
WFPC2 9634
POMS Test Proposal: WFII targeted parallel archive proposal
The parallel opportunities available with WFPC2 in the neighborhood of
bright galaxies are treated in a slightly different way from the
normal pure parallels. Local Group galaxies offer the opportunity for
a closer look at young stellar populations. Narrow-band images in
F656N can be used both to identify young stars via their emission
lines, and to map the gas distribution in star-forming regions. Thus,
the filter F656N is added to the four standard filters. Near more
distant galaxies, up to about 10 Mpc, we can map the population of
globular clusters; for this purpose, F300W is less useful, and only
F450W, F606W, and F814W will be used.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.) None
COMPLETED OPS REQs: None
OPS NOTES EXECUTED:
1198-0 ESHLF20T AND ICDZ5D limit Change @ 040/18:25z
SCHEDULED SUCCESSFUL FAILURE TIMES
FGS GSacq 17 17
FGS REacq 04 04
FHST Update 15 15
LOSS of LOCK
SIGNIFICANT EVENTS: None
