HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5103
PERIOD
COVERED: 5am May 24 - 5am May 25, 2010 (DOY 144/09:00z-145/09:00z)
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
(None)
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSAcq
07
07
FGS
REAcq
09
09
OBAD
with Maneuver 04
04
SIGNIFICANT
EVENTS: (None)
OBSERVATIONS
SCHEDULED:
ACS/WFC
11591
Are
Low-Luminosity Galaxies Responsible for Cosmic Reionization?
Our
group has demonstrated that massive clusters, acting as powerful
cosmic
lenses, can constrain the abundance and properties of
low-luminosity
star-forming sources beyond z~6; such sources are thought
to
be responsible for ending cosmic reionization. The large
magnification
possible in the critical regions of well-constrained
clusters
brings sources into view that lie at or beyond the limits of
conventional
exposures such as the UDF. We have shown that the
combination
of HST and Spitzer is particularly effective in delivering
the
physical properties of these distant sources, constraining their
mass,
age and past star formation history. Indirectly, we therefore gain
a
valuable glimpse to yet earlier epochs. Recognizing the result (and
limitations)
of blank field surveys, we propose a systematic search
through
10
lensing
clusters with ACS/F814W and WFC3/[F110W+F160W] (in conjunction
with
existing deep IRAC data). Our goal is to measure with great
accuracy
the luminosity function at z~7 over a range of at least 3
magnitude,
based on the identification of about 50 lensed galaxies at
6.5<z<8.
Our survey will mitigate cosmic variance and extend the search
both
to lower luminosities and, by virtue of the WFC3/IRAC combination,
to
higher redshift. Thanks to the lensing amplification spectroscopic
follow-up
will be possible and make our findings the most robust prior
to
the era of JWST and the ELTs.
ACS/WFC/WFC3/IR
11142
Revealing
the Physical Nature of Infrared Luminous Galaxies at 0.3<z<2.7
Using
HST and Spitzer
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
contribtuion of mid-to-far IR dust emission is correlated with
morphology
(resolved vs. unresolved).
ACS/WFC/WFC3/IR
11663
Formation
and Evolution of Massive Galaxies in the Richest Environments
at
1.5 < z < 2.0
We
propose to image seven 1.5<z<2 clusters and groups from the IRAC
Shallow
Cluster Survey with WFC3 and ACS in order to study the formation
and
evolution of massive galaxies in the richest environments in the
Universe
in this important redshift range. We will measure the evolution
of
the sizes and morphologies of massive cluster galaxies, as a function
of
redshift, richness, radius and local density. In combination with
allocated
Keck spectroscopy, we will directly measure the dry merger
fraction
in these clusters, as well as the evolution of Brightest
Cluster
Galaxies (BCGs) over this redshift range where clear model
predictions
can be confronted. Finally we will measure both the epoch of
formation
of the stellar populations and the assembly history of that
stellar
mass, the two key parameters in the modern galaxy formation
paradigm.
COS/FUV/COS/NUV
11741
Probing
Warm-Hot Intergalactic Gas at 0.5 < z < 1.3 with a Blind Survey
for
O VI, Ne VIII, Mg X, and Si XII Absorption Systems
Currently
we can only account for half of the baryons (or less) expected
to
be found in the nearby universe based on D/H and CMB observations.
This
"missing baryons problem" is one of the highest-priority challenges
in
observational extragalatic astronomy. Cosmological simulations
suggest
that the baryons are hidden in low-density, shock-heated
intergalactic
gas in the log T = 5 - 7 range, but intensive UV and X-ray
surveys
using O VI, O VII, and O VIII absorption lines have not yet
confirmed
this prediction. We propose to use COS to carry out a
sensitive
survey for Ne VIII and Mg X absorption in the spectra of nine
QSOs
at z(QSO) > 0.89. For the three highest-redshift QSOs, we will also
search
for Si XII. This survey will provide more robust constraints on
the
quantity of baryons in warm-hot intergalactic gas at 0.5 < z < 1.3,
and
the data will provide rich constraints on the metal enrichment,
physical
conditions, and nature of a wide variety of QSO absorbers in
addition
to the warm-hot systems. By comparing the results to other
surveys
at lower redshifts (with STIS, FUSE, and from the COS GTO
programs),
the project will also enable the first study of how these
absorbers
evolve with redshift at z < 1. By combining the program with
follow-up
galaxy redshift surveys, we will also push the study of
galaxy-absorber
relationships to higher redshifts, with an emphasis on
the
distribution of the WHIM with respect to the large-scale matter
distribution
of the universe..
FGS
11789
An
Astrometric Calibration of Population II Distance Indicators
In
2002 HST produced a highly precise parallax for RR Lyrae. That
measurement
resulted in an absolute magnitude, M(V)= 0.61+/-0.11, a
useful
result, judged by the over ten refereed citations each year
since.
It is, however, unsatisfactory to have the direct,
parallax-based,
distance scale of Population II variables based on a
single
star. We propose, therefore, to obtain the parallaxes of four
additional
RR Lyrae stars and two Population II Cepheids, or W Vir
stars.
The Population II Cepheids lie with the RR Lyrae stars on a
common
K-band Period-Luminosity relation. Using these parallaxes to
inform
that relationship, we anticipate a zero-point error of 0.04
magnitude.
This result should greatly strengthen confidence in the
Population
II distance scale and increase our understanding of RR Lyrae
star
and Pop II Cepheid astrophysics.
S/C/WFC3/IR
11929
IR
Dark Current Monitor
Analyses
of ground test data showed that dark current signals are more
reliably
removed from science data using darks taken with the same
exposure
sequences as the science data, than with a single dark current
image
scaled by desired exposure time. Therefore, dark current images
must
be collected using all sample sequences that will be used in
science
observations. These observations will be used to monitor changes
in
the dark current of the WFC3-IR channel on a day-to-day basis, and to
build
calibration dark current ramps for each of the sample sequences to
be
used by GOs in Cycle 17. For each sample sequence/array size
combination,
a median ramp will be created and delivered to the
calibration
database system (CDBS).
STIS/CCD
11845
CCD
Dark Monitor Part 2
Monitor
the darks for the STIS CCD.
STIS/CCD
11847
CCD
Bias Monitor-Part 2
Monitor
the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1,
and
1x1 at gain = 4, to build up high-S/N superbiases and track the
evolution
of hot columns.
STIS/MA1
12079
STIS
PtCr/Ne Lamp Ratios
We
will provide improved information on the ratio of the STIS wavelength
calibration
lamps at all wavelengths. The LINE & HITM1 lamps have faded
by
a factor of several since launch, and at the shortest wavelengths the
fading
is enough to have significantly impacted the S/N of the wavecals.
The
FUV flux of the HITM2 lamp has not been checked since 1997, and so a
detailed
comparison of all three lamps is needed to support a proper
wavelength
calibration for GO proposals.
WFC3/IR
11702
Search
for Very High-z Galaxies with WFC3 Pure Parallel
WFC3
will provide an unprecedented probe to the early universe beyond
the
current redshift frontier. Here we propose a pure parallel program
using
this new instrument to search for Lyman-break galaxies at
6.5<z<8.8
and to probe the epoch of reionization, a hallmark event in
the
history of the early universe. We request 200 orbits, spreading over
30
~ 50 high Galactic latitude visits (|b|>20deg) that last for 4 orbits
and
longer, resulting a total survey area of about 140~230 square
arcminute.
Based on our understanding of the new HST parallel
observation
scheduling process, we believe that the total number of
long-duration
pure parallel visits in Cycle 17 should be sufficient to
accommodate
our program. We waive all proprietary rights to our data,
and
will also make the enhanced data products public in a timely manner.
(1)
We will use both the UVIS and the IR channels, and do not need to
seek
optical data from elsewhere. (2) Our program will likely triple the
size
of the probable candidate samples at z~7 and z~8, and will
complement
other targeted programs aiming at the similar redshift range.
(3)
Being a pure parallel program, our survey will only make very
limited
demand on the scarce HST resources. More importantly, as the
pure
parallel pointings will be at random sight-lines, our program will
be
least affected by the bias due to the large scale structure ("cosmic
variance").
(4) We aim at the most luminous LBG population, and will
address
the bright-end of the luminosity function at z~8 and z~7. We
will
constrain the value of L* in particular, which is critical for
understanding
the star formation process and the stellar mass assembly
history
in the first few hundred million years of the universe. (5) The
candidates
from our survey, most of which will be the brightest ones
that
any surveys would be able to find, will have the best chance to be
spectroscopically
confirmed at the current 8--10m telescopes. (6) We
will
also find a large number of extremely red, old galaxies at
intermediate
redshifts, and the fine spatial resolution offered by the
WFC3
will enable us constrain their formation history based on the study
of
their morphology, and hence shed light on their connection to the
very
early galaxies in the universe.
WFC3/UVI
11556
Investigations
of the Pluto System
We
propose a set of high SNR observations of the Pluto system that will
provide
improved lightcurves, orbits, and photometric properties of Nix
and
Hydra. The key photometric result for Nix and Hydra will be a vastly
improved
lightcurve shape and rotation period to test if the objects are
in
synchronous rotation or not. A second goal of this program will be to
retrieve
a new epoch of albedo map for the surface of Pluto. These
observations
will also improve masses and in some case densities for the
bodies
in the Pluto system.
WFC3/UVI
11702
Search
for Very High-z Galaxies with WFC3 Pure Parallel
WFC3
will provide an unprecedented probe to the early universe beyond
the
current redshift frontier. Here we propose a pure parallel program
using
this new instrument to search for Lyman-break galaxies at
6.5<z<8.8
and to probe the epoch of reionization, a hallmark event in
the
history of the early universe. We request 200 orbits, spreading over
30
~ 50 high Galactic latitude visits (|b|>20deg) that last for 4 orbits
and
longer, resulting a total survey area of about 140~230 square
arcminute.
Based on our understanding of the new HST parallel
observation
scheduling process, we believe that the total number of
long-duration
pure parallel visits in Cycle 17 should be sufficient to
accommodate
our program. We waive all proprietary rights to our data,
and
will also make the enhanced data products public in a timely manner.
(1)
We will use both the UVIS and the IR channels, and do not need to
seek
optical data from elsewhere. (2) Our program will likely triple the
size
of the probable candidate samples at z~7 and z~8, and will
complement
other targeted programs aiming at the similar redshift range.
(3)
Being a pure parallel program, our survey will only make very
limited
demand on the scarce HST resources. More importantly, as the
pure
parallel pointings will be at random sight-lines, our program will
be
least affected by the bias due to the large scale structure ("cosmic
variance").
(4) We aim at the most luminous LBG population, and will
address
the bright-end of the luminosity function at z~8 and z~7. We
will
constrain the value of L* in particular, which is critical for
understanding
the star formation process and the stellar mass assembly
history
in the first few hundred million years of the universe. (5) The
candidates
from our survey, most of which will be the brightest ones
that
any surveys would be able to find, will have the best chance to be
spectroscopically
confirmed at the current 8--10m telescopes. (6) We
will
also find a large number of extremely red, old galaxies at
intermediate
redshifts, and the fine spatial resolution offered by the
WFC3
will enable us constrain their formation history based on the study
of
their morphology, and hence shed light on their connection to the
very
early galaxies in the universe.
WFC3/UVI
11730
Continued
Proper Motions of the Magellanic Clouds: Orbits, Internal
Kinematics,
and Distance
In
Cycles 11 and 13 we obtained two epochs of ACS/HRC data for fields in
the
Magellanic Clouds centered on background quasars. We used these data
to
determine the proper motions of the LMC and SMC to better than 5% and
15%
respectively. The results had a number of unexpected implications
for
the Milky Way-LMC-SMC system and received considerable attention in
the
literature and in the press. The implied three-dimensional
velocities
are larger than previously believed and close to the escape
velocity
in a standard 10^12 solar mass Milky Way dark halo. Our orbit
calculations
suggest the Clouds may not be bound to the Milky Way or may
just
be on their first passage, both of which are unexpected in view of
traditional
interpretations of the Magellanic Stream. Alternatively, the
Milky
Way dark halo may be a factor two more massive than previously
believed,
which would be surprising in view of other observational
constraints.
Also, the relative velocity between the LMC and SMC was
larger
than expected, leaving open the possibility that the Clouds may
not
be bound to each other. To further verify and refine our results we
requested
an additional epoch data in Cycle 16 which is being executed
with
WFPC2/PC due to the failure of ACS. A detailed analysis of one LMC
field
shows that the field proper motion using all three epochs of data
is
consistent within 1-sigma with the two-epoch data, thus verifying
that
there are no major systematic effects in our previous measurements.
The
random errors, however, are only smaller by a factor of 1.4 because
of
the relatively large errors in the WFPC2 data. A prediction for a
fourth
epoch with measurement errors similar to epochs 1 and 2 shows
that
the uncertainties will improve by a factor of 3. This will allow us
to
better address whether the Clouds are indeed bound to each other and
to
the Milky Way. It will also allow us to constrain the internal
motions
of various populations within the Clouds, and to determine a
distance
to the LMC using rotational parallax. Continuation of this
highly
successful program is therefore likely to provide important
additional
insights. Execution in SNAPshot mode guarantees maximally
efficient
use of HST resources.
WFC3/UVI
11905
WFC3
UVIS CCD Daily Monitor
The
behavior of the WFC3 UVIS CCD will be monitored daily with a set of
full-frame,
four-amp bias<BR>and dark frames. A smaller set of 2Kx4K
subarray
biases are acquired at less frequent intervals<BR>throughout
the
cycle to support subarray science observations. The internals from
this
proposal,<BR>along with those from the anneal procedure (11909),
will
be used to generate the necessary superbias<BR>and superdark
reference
files for the calibration pipeline (CDBS).
WFC3/UVI
11908
Cycle
17: UVIS Bowtie Monitor
Ground
testing revealed an intermittent hysteresis type effect in the
UVIS
detector (both CCDs) at the level of ~1%, lasting hours to days.
Initially
found via an unexpected bowtie-shaped feature in flatfield
ratios,
subsequent lab tests on similar e2v devices have since shown
that
it is also present as simply an overall offset across the entire
CCD,
i.e., a QE offset without any discernable pattern. These lab tests
have
further revealed that overexposing the detector to count levels
several
times full well fills the traps and effectively neutralizes the
bowtie.
Each visit in this proposal acquires a set of three 3x3 binned
internal
flatfields: the first unsaturated image will be used to detect
any
bowtie, the second, highly-exposed image will neutralize the bowtie
if
it is present, and the final image will allow for verification that
the
bowtie is gone.