HUBBLE SPACE TELESCOPE - Continuing to collect World
Class Science
DAILY REPORT # 4498
PERIOD COVERED: UT November 30 December 1, 2, 2007 (DOY
334,335,336)
OBSERVATIONS SCHEDULED
NIC1/NIC2/NIC3 8794
NICMOS Post-SAA calibration - CR Persistence Part 5
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 DARKs. 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.
WFPC2 11361
Hubble Heritage Observations of Mars at 2007 Opposition
We will obtain images of Mars at opposition in December
2007.
NIC3 11334
NICMOS Cycle 16 Spectrophotometry
Observation of the three primary WD flux standards must
be repeated to
refine the NICMOS absolute calibration and monitor for
sensitivity
degradation. So far, NICMOS grism spectrophotometry is available
for
only ~16 stars with good STIS spectra at shorter wavelengths. There
are
more in the HST CALSPEC standard star data base with good STIS
spectra
that would also become precise IR standards with NICMOS absolute
SED
measurements. Monitoring the crucial three very red stars (M, L, T)
for
variability and better S/N in the IR. Apparent variability
was
discovered at shorter wavelengths during the ACS cross-calibration
work
that revealed a ~2% discrepancy of the cool star fluxes with respect
to
the hot primary WD standards. About a third of these stars are
bright
enough to do in one orbit, the rest require 2 orbits.
ACS/SBC 11323
Improved Wavelengths Calibration of SBC Prisms
We propose to check and improve the wavelength
calibration of the SBC
PR110L and PR130L prisms by observing an additional
calibrator target
for which observations failed in Cycle 14. Previous
calibration
programs included two QSOs at redshifts z = 0.098 (PG1404+226), z
=
0.168 (PG1322+659), and z=0.234 (PB5723), but the observation of
a
further QSO at z = 0.313 (3C249.1) failed. This proposals aims to
obtain
observations of 3C249.1. The observations of PB5723 show
adequate
agreement of the wavelength of the Lyman alphaline as a function
of
position but, while the rms is around 0.5 pixel, some spectra
show
evidence of stretching of the wavelength scale. Given the
steeply
increased use of the SBC prims in Cycle 16 it is desirable to
obtain
additional observations in order to check the existing
calibration,
identify any trends with time and thus improve the SBC prism
wavelength
calibration.
S/C 11320
NICMOS Focus Monitoring Cycle 16
This program is a version of the standard focus sweep
used since cycle
7. It has been modified to go deeper and uses more narrow
filters for
improved focus determination. A new source was added in Cycle 14
in
order to accommodate 2-gyro mode: the open cluster NGC1850. This
source
is part of the current proposal. The old target, the open
cluster
NGC3603, will be used whenever available and the new target used to
fill
the periods when NGC3603 is not visible. Steps: a) Use refined
target
field positions as determined from cycle 7 calibrations b)
Use
MULTIACCUM sequences of sufficient dynamic range to account for
defocus
c) Do a 17-point focus sweep, +/- 8mm about the PAM mechanical
zeropoint
for each cameras 1 and 2, in 1.0mm steps. For NIC3 we step from
-0.5mm
to -9.5mm relative to mechanical zero, in steps of 1.0mm. d) Use PAM
X/Y
tilt and OTA offset slew compensations refined from previous
focus
monitoring/optical alignment activities
FGS 11212
Filling the Period Gap for Massive Binaries
The current census of binaries among the massive O-type
stars is
seriously incomplete for systems in the period range from years
to
millennia because the radial velocity variations are too small and
the
angular separations too close for easy detection. Here we propose
to
discover binaries in this observational gap through a Faint
Guidance
Sensor SNAP survey of relatively bright targets listed in the
Galactic O
Star Catalog. Our primary goal is to determine the binary
frequency
among those in the cluster/association, field, and runaway groups.
The
results will help us assess the role of binaries in massive
star
formation and in the processes that lead to the ejection of
massive
stars from their natal clusters. The program will also lead to
the
identification of new, close binaries that will be targets of long
term
spectroscopic and high angular resolution observations to
determine
their masses and distances. The results will also be important for
the
interpretation of the spectra of suspected and newly identified
binary
and multiple systems.
WFPC2 11202
The Structure of Early-type Galaxies: 0.1-100 Effective
Radii
The structure, formation and evolution of early-type
galaxies is still
largely an open problem in cosmology: how does the Universe
evolve from
large linear scales dominated by dark matter to the highly
non-linear
scales of galaxies, where baryons and dark matter both play
important,
interacting, roles? To understand the complex physical
processes
involved in their formation scenario, and why they have the
tight
scaling relations that we observe today {e.g. the Fundamental Plane},
it
is critically important not only to understand their stellar
structure,
but also their dark-matter distribution from the smallest to the
largest
scales. Over the last three years the SLACS collaboration has
developed
a toolbox to tackle these issues in a unique and encompassing way
by
combining new non-parametric strong lensing techniques,
stellar
dynamics, and most recently weak gravitational lensing,
with
high-quality Hubble Space Telescope imaging and VLT/Keck
spectroscopic
data of early-type lens systems. This allows us to break
degeneracies
that are inherent to each of these techniques separately and
probe the
mass structure of early-type galaxies from 0.1 to 100 effective
radii.
The large dynamic range to which lensing is sensitive allows us both
to
probe the clumpy substructure of these galaxies, as well as
their
low-density outer haloes. These methods have convincingly
been
demonstrated, by our team, using smaller pilot-samples of SLACS
lens
systems with HST data. In this proposal, we request observing time
with
WFPC2 and NICMOS to observe 53 strong lens systems from SLACS, to
obtain
complete multi-color imaging for each system. This would bring the
total
number of SLACS lens systems to 87 with completed HST imaging
and
effectively doubles the known number of galaxy-scale strong lenses.
The
deep HST images enable us to fully exploit our new techniques, beat
down
low-number statistics, and probe the structure and evolution
of
early-type galaxies, not only with a uniform data-set an order
of
magnitude larger than what is available now, but also with a
fully
coherent and self-consistent methodological approach!
WFPC2 11178
Probing Solar System History with Orbits, Masses, and
Colors of
Transneptunian Binaries
The recent discovery of numerous transneptunian binaries
{TNBs} opens a
window into dynamical conditions in the protoplanetary disk
where they
formed as well as the history of subsequent events which sculpted
the
outer Solar System and emplaced them onto their present day
heliocentric
orbits. To date, at least 47 TNBs have been discovered, but only
about a
dozen have had their mutual orbits and separate colors
determined,
frustrating their use to investigate numerous important
scientific
questions. The current shortage of data especially cripples
scientific
investigations requiring statistical comparisons among the
ensemble
characteristics. We propose to obtain sufficient astrometry
and
photometry of 23 TNBs to compute their mutual orbits and system
masses
and to determine separate primary and secondary colors, roughly
tripling
the sample for which this information is known, as well as extending
it
to include systems of two near-equal size bodies. To make the
most
efficient possible use of HST, we will use a Monte Carlo technique
to
optimally schedule our observations.
NIC2 11142
Revealing the Physical Nature of Infrared Luminous
Galaxies at 0.3
We aim to determine physical properties of IR luminous
galaxies at
0.3<z<2.7 by requesting coordinated HST/NIC2 and MIPS 70um
observations
of a unique, 24um flux- limited sample with complete Spitzer
mid-IR
spectroscopy. The 150 sources investigated in this program have
S{24um}
> 0.8mJy and their mid-IR spectra have already provided the
majority
targets with spectroscopic redshifts {0.3<z<2.7}. The
proposed
150~orbits of NIC2 and 66~hours of MIPS 70um will provide the
physical
measurements of the light distribution at the rest-frame ~8000A
and
better estimates of the bolometric luminosity. Combining
these
parameters together with the rich suite of spectral diagnostics from
the
mid-IR spectra, we will {1} measure how common mergers are among
LIRGs
and ULIRGs at 0.3<z<2.7, and establish if major mergers are the
drivers
of z>1 ULIRGs, as in the local Universe. {2} study the
co-evolution of
star formation and blackhole accretion by investigating the
relations
between the fraction of starburst/AGN measured from mid-IR spectra
vs.
HST morphologies, L{bol} and z. {3} obtain the current best estimates
of
the far- IR emission, thus L{bol} for this sample, and establish if
the
relative contribution of mid-to- far IR dust emission is correlated
with
morphology {resolved vs. unresolved}.
WFPC2 11130
AGNs with Intermediate-mass Black Holes: Testing the
Black Hole-Bulge
Paradigm, Part II
The recent progress in the study of central black holes
in galactic
nuclei has led to a general consensus that supermassive
{10^6-10^9 solar
mass} black holes are closely connected with the formation
and
evolutionary history of large galaxies, especially their
bulge
component. Two outstanding issues, however, remain unresolved.
Can
central black holes form in the absence of a bulge? And does the
mass
function of central black holes extend below 10^6 solar
masses?
Intermediate-mass black holes {<10^6 solar masses}, if they exist,
may
offer important clues to the nature of the seeds of supermassive
black
holes. Using the SDSS, our group has successfully uncovered a
new
population of AGNs with intermediate-mass black holes that reside
in
low-luminosity galaxies. However, very little is known about
the
detailed morphologies or structural parameters of the host
galaxies
themselves, including the crucial question of whether they have
bulges
or not. Surprisingly, the majority of the targets of our Cycle 14
pilot
program have structural properties similar to dwarf elliptical
galaxies.
The statistics from this initial study, however, are really too
sparse
to reach definitive conclusions on this important new class of
black
holes. We wish to extend this study to a larger sample, by using
the
Snapshot mode to obtain WFPC2 F814W images from a parent sample of
175
AGNs with intermediate-mass black holes selected from our final
SDSS
search. We are particularly keen to determine whether the hosts
contain
bulges, and if so, how the fundamental plane properties of the
host
depend on the mass of their central black holes. We will
also
investigate the environment of this unique class of AGNs.
WFPC2 11125
The Dynamical Evolution of Globular Clusters
Globular clusters evolve through dynamical interactions,
with primordial
binaries extending the time until core collapse by up to an
order of
magnitude, depending on the initial binary fraction. These
dynamical
interactions plus mass segregation causes the binary fraction to
rise in
the core but fall at larger radii. We hope to eventually test
these
broad predictions by comparing them to the binary properties
for
globular clusters at different states of evolution, defined by the
ratio
of their age to the dynamical relaxation time at the half-light
radius.
The most important unknown aspects in the modeling process are
the
initial conditions of binaries in the cluster. Here we propose
to
determine the initial binary fraction as a function of radius
by
studying three of the dynamically youngest globular clusters {NGC
5053,
NGC 5466, and NGC 5897}. The presence of binaries thickens the
Main
Sequence in a color-magnitude diagram, which can be detected with
deep
multicolor images.
WFPC2 11103
A Snapshot Survey of The Most Massive Clusters of
Galaxies
We propose the continuation of our highly successful
SNAPshot survey of
a sample of 125 very X-ray luminous clusters in the
redshift range
0.3-0.7. As demonstrated by the 25 snapshots obtained so far
in Cycle14
and Cycle15 these systems frequently exhibit strong
gravitational
lensing as well as spectacular examples of violent galaxy
interactions.
The proposed observations will provide important constraints on
the
cluster mass distributions, the physical nature of galaxy-galaxy
and
galaxy-gas interactions in cluster cores, and a set of optically
bright,
lensed galaxies for further 8-10m spectroscopy. All of our
primary
science goals require only the detection and characterization
of
high-surface-brightness features and are thus achievable even at
the
reduced sensitivity of WFPC2. Because of their high redshift and
thus
compact angular scale our target clusters are less adversely affected
by
the smaller field of view of WFPC2 than more nearby
systems.
Acknowledging the broad community interest in this sample we waive
our
data rights for these observations. Due to a clerical error at STScI
our
approved Cycle15 SNAP program was barred from execution for 3 months
and
only 6 observations have been performed to date - reinstating this
SNAP
at Cycle16 priority is of paramount importance to reach
meaningful
statistics.
WFPC2 11079
Treasury Imaging of Star Forming Regions in the Local
Group:
Complementing the GALEX and NOAO Surveys
We propose to use WFPC2 to image the most interesting
star-forming
regions in the Local Group galaxies, to resolve their young
stellar
populations. We will use a set of filters including F170W, which
is
critical to detect and characterize the most massive stars, to whose
hot
temperatures colors at longer wavelengths are not sensitive.
WFPC2's
field of view ideally matches the typical size of the
star-forming
regions, and its spatial resolution allows us to measure
individual
stars, given the proximity of these galaxies. The resulting H-R
diagrams
will enable studies of star-formation properties in these regions,
which
cover largely differing metallicities {a factor of 17, compared to
the
factor of 4 explored so far} and characteristics. The results
will
further our understanding of the star-formation process, of
the
interplay between massive stars and environment, the properties of
dust,
and will provide the key to interpret integrated measurements
of
star-formation indicators {UV, IR, Halpha} available for
several
hundreds more distant galaxies. Our recent deep surveys of
these
galaxies with GALEX {FUV, NUV} and ground-based imaging {UBVRI,
Halpha,
[OIII] and [SII]} provided the identification of the most relevant
SF
sites. In addition to our scientific analysis, we will provide
catalogs
of HST photometry in 6 bands, matched corollary ground-based data,
and
UV, Halpha and IR integrated measurements of the associations,
for
comparison of integrated star-formation indices to the
resolved
populations. We envisage an EPO component.
WFPC2 11029
WFPC2 CYCLE 15 Intflat Linearity Check and Filter
Rotation Anomaly
Monitor
Intflat observations will be taken to provide a
linearity check: the
linearity test consists of a series of intflats in
F555W, in each gain
and each shutter. A combination of intflats, visflats,
and earthflats
will be used to check the repeatability of filter wheel
motions.
{Intflat sequences tied to decons, visits 1-18 in prop 10363, have
been
moved to the cycle 15 decon proposal xxxx for easier scheduling.}
Note:
long-exposure WFPC2 intflats must be scheduled during ACS anneals
to
prevent stray light from the WFPC2 lamps from contaminating long
ACS
external exposures.
WFPC2 11027
Visible Earth Flats
This proposal monitors flatfield stability. This
proposal obtains
sequences of Earth streak flats to construct high quality
flat fields
for the WFPC2 filter set. These flat fields will allow mapping of
the
OTA illumination pattern and will be used in conjunction with
previous
internal and external flats to generate new pipeline superflats.
These
Earth flats will complement the Earth flat data obtained during
cycles
4-14.
WFPC2 11020
Cycle 15 Focus Monitor
The focus of HST is measured primarily with ACS/HRC over
full CVZ orbits
to obtain accurate mean focus values via a well sampled
breathing curve.
Coma and astigmatism are also determined from the same data
in order to
further understand orbital effects on image quality and
optical
alignments. To monitor the stability of ACS to WFPC2 relative
focii,
we've carried over from previous focus monitor programs
parallel
observations taken with the two cameras at suitable orientations
of
previously observed targets, and interspersed them with the HRC
CVZ
visits.
WFPC2 11011
Dissecting An Accretion Disk
We will use 5 epochs of CXO and HST imaging to determine
the X-ray and
UV size of the accretion disk of the lensed quasar
RXJ1131--1231 using
microlensing. Based on preliminary data, we find that the
X-ray source
is roughly 1/10 the size of the accretion disk in the rest-frame
B-band.
The new observations will significantly reduce the uncertainties in
this
estimate, provide a comparison between the size of the X-ray source
and
the size of the accretion disk in the rest frame ultraviolet, and
have
the signal-to-noise ratio necessary to begin examining the size of
the
hard and soft-band X-ray emission regions separately. The results
will
quantitatively test accretion disk theory and X-ray emission
mechanisms.
WFPC2 10915
ACS Nearby Galaxy Survey
Existing HST observations of nearby galaxies comprise a
sparse and
highly non-uniform archive, making comprehensive comparative
studies
among galaxies essentially impossible. We propose to secure
HST's
lasting impact on the study of nearby galaxies by undertaking
a
systematic, complete, and carefully crafted imaging survey of
ALL
galaxies in the Local Universe outside the Local Group. The
resulting
images will allow unprecedented measurements of: {1} the star
formation
history {SFH} of a >100 Mpc^3 volume of the Universe with a
time
resolution of Delta[log{t}]=0.25; {2} correlations between
spatially
resolved SFHs and environment; {3} the structure and properties of
thick
disks and stellar halos; and {4} the color distributions, sizes,
and
specific frequencies of globular and disk clusters as a function
of
galaxy mass and environment. To reach these goals, we will use
a
combination of wide-field tiling and pointed deep imaging to
obtain
uniform data on all 72 galaxies within a volume-limited sample
extending
to ~3.5 Mpc, with an extension to the M81 group. For each galaxy,
the
wide-field imaging will cover out to ~1.5 times the optical radius
and
will reach photometric depths of at least 2 magnitudes below the tip
of
the red giant branch throughout the limits of the survey volume.
One
additional deep pointing per galaxy will reach SNR~10 for red
clump
stars, sufficient to recover the ancient SFH from the
color-magnitude
diagram. This proposal will produce photometric information
for ~100
million stars {comparable to the number in the SDSS survey} and
uniform
multi- color images of half a square degree of sky. The
resulting
archive will establish the fundamental optical database for
nearby
galaxies, in preparation for the shift of high- resolution imaging
to
the near-infrared.
ACS/SBC 10907
New Sightlines for the Study of Intergalactic Helium: A
Dozen
High-Confidence, UV-Bright Quasars from SDSS/GALEX
The reionization of intergalactic helium is thought to
have occurred
between redshifts of about 3 and 4. Detailed study of HeII
Lyman-alpha
absorption toward a handful quasars at 2.7<z<3.3
demonstrates the great
potential of such probes of the IGM, but the current
critically-small
sample limits confidence in resulting cosmological
inferences. The
requisite unobscured quasar sightlines to high-redshift are
extremely
rare, especially due to severe absorption in random
intervening
Lyman-limit systems, but SDSS provides thousands of z>3.1
quasars
potentially suitable for HeII studies. We have cross-correlated
SDSS
quasars with GALEX UV sources to obtain a dozen new,
very
high-confidence, candidate quasars/sightlines {z=3.1 to 4.1}
potentially
useful for detailed HeII studies even with current HST
instruments. We
propose brief, 2-orbit per target, reconnaissance spectral
exposures
with the ACS SBC prism to definitively verify UV flux down to the
HeII
break. Our combined SDSS/GALEX selection insures a very high-yield
of
confirmations, as the quasars are already known to be UV-bright
from
broadband GALEX images. The additional sightlines, extending to
very
high-redshift, will directly enable ensemble spectral stacks, as well
as
long exposure follow-up spectra, at high S/N with the
ACS/SBC
ultraviolet prisms {or perhaps STIS or COS later}, to
confidently
measure the spectrum and evolution of the ionizing background
radiation,
the evolution of HeII opacity, and the density of intergalactic
baryons.
NIC2 10896
An Efficient ACS Coronagraphic Survey for Debris Disks
around Nearby
Stars
We propose to finish our Cycle 11 optical survey for
nearby debris disks
using the ACS/HRC coronagraph. Out of 43 orbits
originally proposed for
the survey, 23 orbits were allocated, leading to a
survey of 22 stars,
from which two new debris disks were imaged for the first
time. Our
analysis of the initial survey gives an empirical estimate for
the
detection rate of debris disks relative to heliocentric distance
and
dust optical depth. Our target list for Cycle 15 is now optimized
to
yield more frequent disk detections. Likewise our observing strategy
is
improved to maximize sensitivity per telescope orbit
allocated.
Therefore we present the most efficient survey possible. The
scientific
motivation is to obtain scattered light images of previously
unresolved
debris disks to determine their viewing geometry and
physical
architecture, both of which may characterize the underlying
planetary
system. We choose 25 debris disk targets for which we predict
a
detection rate of 25% ? 5%. Four targets have extrasolar planets
from
which the viewing geometry revealed by a disk detection will resolve
the
v sin{i} ambiguity in the planet masses. These targets present
the
remarkable opportunity of finally seeing a debris disk in system
with
known planets.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11082 - REAcq (1,2,2) failed to RGA
Hold
At AOS (334/23:25:15) observed that REAcq (1,2,2) scheduled from
22:59:42 - 23:07:17 had failed to RGA Hold due to QSTOP &
QF1STOPF flags
on
FGS 1. No 486 ESB messages were received. Due to LOS, the data from
OBAD 1 & 2 is unavailable till an engineering data dump is
performed.
OBAD MAP data showed the following results: V1 -13.66, V2 -5.48,
V3
-5.82, RSS 15.83.
11084 - REACQ(1,2,1) failed, Search Radius Limit
exceeded on FGS 1
REACQ(1,2,1) at 335/21:25:44 failed at 21:31:03 with search radius
limit
exceeded
on FGS 1. Three 486 status buffer 1805
(T2G_MOVING_TARGET_DETECTED) and one "A05" message (FGS Coarse
Track
failed- search Radius Limit exceeded) were received.
Primary
GSACQ(1,2,1) at 19:51:59 was successful.
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSacq
24
24
FGS REacq
14 12
OBAD with Maneuver
76
76
SIGNIFICANT EVENTS: (None)