HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5164
PERIOD
COVERED: 5am August 19 - 5am August 20, 2010 (DOY 231/09:00z-232/09:00z)
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
5
5
FGS
REAcq
9
9
OBAD
with Maneuver
3
3
SIGNIFICANT
EVENTS: (None)
OBSERVATIONS
SCHEDULED:
COS/NUV
11894
NUV
Detector Dark Monitor
The
purpose of this proposal is to measure the NUV detector dark rate by
taking
long science exposures with no light on the detector. The
detector
dark rate and spatial distribution of counts will be compared
to
pre-launch and SMOV data in order to verify the nominal operation of
the
detector. Variations of count rate as a function of orbital position
will
be analyzed to find dependence of dark rate on proximity to the
SAA.
Dependence of dark rate as function of time will also be tracked.
COS/NUV/FUV
11598
How
Galaxies Acquire their Gas: A Map of Multiphase Accretion and
Feedback
in Gaseous Galaxy Halos
We
propose to address two of the biggest open questions in galaxy
formation
- how galaxies acquire their gas and how they return it to the
IGM
- with a concentrated COS survey of diffuse multiphase gas in the
halos
of SDSS galaxies at z = 0.15 - 0.35. Our chief science goal is to
establish
a basic set of observational facts about the physical state,
metallicity,
and kinematics of halo gas, including the sky covering
fraction
of hot and cold material, the metallicity of infall and
outflow,
and correlations with galaxy stellar mass, type, and color -
all
as a function of impact parameter from 10 - 150 kpc. Theory suggests
that
the bimodality of galaxy colors, the shape of the luminosity
function,
and the mass-metallicity relation are all influenced at a
fundamental
level by accretion and feedback, yet these gas processes are
poorly
understood and cannot be predicted robustly from first
principles.
We lack even a basic observational assessment of the
multiphase
gaseous content of galaxy halos on 100 kpc scales, and we do
not
know how these processes vary with galaxy properties. This ignorance
is
presently one of the key impediments to understanding galaxy
formation
in general. We propose to use the high-resolution gratings
G130M
and G160M on the Cosmic Origins Spectrograph to obtain sensitive
column
density measurements of a comprehensive suite of multiphase ions
in
the spectra of 43 z < 1 QSOs lying behind 43 galaxies selected from
the
Sloan Digital Sky Survey. In aggregate, these sightlines will
constitute
a statistically sound map of the physical state and
metallicity
of gaseous halos, and subsets of the data with cuts on
galaxy
mass, color, and SFR will seek out predicted variations of gas
properties
with galaxy properties. Our interpretation of these data will
be
aided by state-of-the-art hydrodynamic simulations of accretion and
feedback,
in turn providing information to refine and test such models.
We
will also use Keck, MMT, and Magellan (as needed) to obtain optical
spectra
of the QSOs to measure cold gas with Mg II, and optical spectra
of
the galaxies to measure SFRs and to look for outflows. In addition to
our
other science goals, these observations will help place the Milky
Way's
population of multiphase, accreting High Velocity Clouds (HVCs)
into
a global context by identifying analogous structures around other
galaxies.
Our program is designed to make optimal use of the unique
capabilities
of COS to address our science goals and also generate a
rich
dataset of other absorption-line systems.
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/CCD/MA1/MA2
11569
Probing
the Atomic and Molecular Inventory of a Beta-Pic Analog, the
Young,
Edge-On Debris Disk of HD32297
Edge-on,
optically thin, debris disks provide unique opportunities to
probe
physical properties of the disk itself. Using the host star as the
background
source, trace atomic and molecular disk species can be
detected
in absorption. Redfield (2007) found that the recently
discovered
edge- on system, HD32297, has the strongest NaI absorption
feature
of any known debris disk, 5 times the level observed toward beta
Pic,
the canonical edge-on debris disk. Roberge et al. (2006) compiled
the
only comprehensive chemical inventory of a debris disk, using beta
Pic,
and found that carbon was surprisingly overabundant, which has
important
implications for the physical structure and support of a
stable
gas disk. What is severely lacking are comparison observations to
determine
if such an abundance pattern is typical of debris disk
systems.
HD32297 represents the best opportunity to make such a
comparative
study and perform a comprehensive gas inventory of a debris
disk,
due to its high NaI column density. The UV is critical for this
work
due to the large number of strong transitions (almost 50 ions and
molecules
are accessible) that are located in, and often only in, the
UV.
These observations will provide a much needed comparison dataset for
addressing
the gas chemistry of debris disk systems that are at the
critical
stage, near the end of planet formation, and in the process of
clearing
their interplanetary environments.
STIS/CCD/MA1/MA2
11616
The
Disks, Accretion, and Outflows (DAO) of T Tau Stars
Classical
T Tauri stars undergo magnetospheric accretion, power
outflows,
and possess the physical and chemical conditions in their
disks
to give rise to planet formation. Existing high resolution FUV
spectra
verify that this spectral region offers unique diagnostics of
these
processes, which have the potential to significantly advance our
understanding
of the interaction of a star and its accretion disk. To
date
the limited results are intriguing, with dramatic differences in
kinematic
structure in lines ranging from C IV to H2 among the few stars
that
have been observed. We propose to use HST/COS to survey the disks,
outflows,
and accretion (the DAO) of 26 CTTS and 6 WTTS in the FUV at
high
spectral resolution. A survey of this size is essential to
establish
how properties of accretion shocks, winds and disk irradiation
depend
on disk accretion rate. Specifically, our goals are to (1)
measure
the radiation from and understand the physical properties of the
gas
very near the accretion shock as a function of accretion rate using
emission
line profiles of hot lines (C IV, Si IV, N V, and He II); (2)
measure
the opacity, velocity, and temperature at the base of the
outflow
to constrain outflow models using wind absorption features; and
(3)
characterize the radiation incident on disks and protoplanetary
atmospheres
using H2 line and continuum emission and reconstructed
bright
Ly-alpha line emission.
STIS/MA1/MA2
11857
STIS
Cycle 17 MAMA Dark Monitor
This
proposal monitors the behavior of the dark current in each of the
MAMA
detectors.
The
basic monitor takes two 1380s ACCUM darks each week with each
detector.
However, starting Oct 5, pairs are only included for weeks
that
the LRP has external MAMA observations planned. The weekly pairs of
exposures
for each detector are linked so that they are taken at
opposite
ends of the same SAA free interval. This pairing of exposures
will
make it easier to separate long and short term temporal variability
from
temperature dependent changes.
For
both detectors, additional blocks of exposures are taken once every
six
months. These are groups of five 1314s FUV-MAMA Time-Tag darks or
five
3x315s NUV ACCUM darks distributed over a single SAA-free interval.
This
will give more information on the brightness of the FUV MAMA dark
current
as a function of the amount of time that the HV has been on, and
for
the NUV MAMA will give a better measure of the short term
temperature
dependence.
WFC3/IR
11696
Infrared
Survey of Star Formation Across Cosmic Time
We
propose to use the unique power of WFC3 slitless spectroscopy to
measure
the evolution of cosmic star formation from the end of the
reionization
epoch at z>6 to the close of the galaxy- building era at
z~0.3.Pure
parallel observations with the grisms have proven to be
efficient
for identifying line emission from galaxies across a broad
range
of redshifts. The G102 grism on WFC3 was designed to extend this
capability
to search for Ly-alpha emission from the first galaxies.
Using
up to 250 orbits of pure parallel WFC3 spectroscopy, we will
observe
about 40 deep (4-5 orbit) fields with the combination of G102
and
G141, and about 20 shallow (2-3 orbit) fields with G141 alone.
Our
primary science goals at the highest redshifts are: (1) Detect Lya
in
~100 galaxies with z>5.6 and measure the evolution of the Lya
luminosity
function, independent of of cosmic variance; 2) Determine the
connection
between emission line selected and continuum-break selected
galaxies
at these high redshifts, and 3) Search for the proposed
signature
of neutral hydrogen absorption at re-ionization. At
intermediate
redshifts we will (4) Detect more than 1000 galaxies in
Halpha
at 0.5<z<1.8 to measure the evolution of the extinction-corrected
star
formation density across the peak epoch of star formation. This is
over
an order-of-magnitude improvement in the current statistics, from
the
NICMOS Parallel grism survey. (5) Trace ``cosmic downsizing" from
0.5<z<2.2;
and (6) Estimate the evolution in reddening and metallicty in
star-
forming galaxies and measure the evolution of the Seyfert
population.
For hundreds of spectra we will be able to measure one or
even
two line pair ratios -- in particular, the Balmer decrement and
[OII]/[OIII]
are sensitive to gas reddening and metallicity. As a bonus,
the
G102 grism offers the possibility of detecting Lya emission at
z=7-8.8.
To
identify single-line Lya emitters, we will exploit the wide
0.8--1.9um
wavelength coverage of the combined G102+G141 spectra. All
[OII]
and [OIII] interlopers detected in G102 will be reliably separated
from
true LAEs by the detection of at least one strong line in the G141
spectrum,
without the need for any ancillary data. We waive all
proprietary
rights to our data and will make high-level data products
available
through the ST/ECF.
WFC3/IR
11926
IR
Zero Points
We
will measure and monitor the zeropoints through the IR filters using
observations
of the white dwarf standard stars, GD153, GD71 and GD191B2B
and
the solar analog standard star, P330E. Data will be taken monthly
during
Cycle 17. Observations of the star cluster, NGC 104, are made
twice
to check color transformations. We expect an accuracy of 2% in the
wide
filter zeropoints relative to the HST photometric system, and 5% in
the
medium- and narrow-band filters.
WFC3/UVIS
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 and dark frames. A smaller set of 2Kx4K
subarray
biases are acquired at less frequent intervals throughout the
cycle
to support subarray science observations. The internals from this
proposal,
along with those from the anneal procedure (Proposal 11909),
will
be used to generate the necessary superbias and superdark reference
files
for the calibration pipeline (CDBS).
WFC3/UVIS/IR
11644
A
Dynamical-Compositional Survey of the Kuiper Belt: A New Window Into
the
Formation of the Outer Solar System
The
eight planets overwhelmingly dominate the solar system by mass, but
their
small numbers, coupled with their stochastic pasts, make it
impossible
to construct a unique formation history from the dynamical or
compositional
characteristics of them alone. In contrast, the huge
numbers
of small bodies scattered throughout and even beyond the
planets,
while insignificant by mass, provide an almost unlimited number
of
probes of the statistical conditions, history, and interactions in
the
solar system. To date, attempts to understand the formation and
evolution
of the Kuiper Belt have largely been dynamical simulations
where
a hypothesized starting condition is evolved under the
gravitational
influence of the early giant planets and an attempt is
made
to reproduce the current observed populations. With little
compositional
information known for the real Kuiper Belt, the test
particles
in the simulation are free to have any formation location and
history
as long as they end at the correct point. Allowing compositional
information
to guide and constrain the formation, thermal, and
collisional
histories of these objects would add an entire new dimension
to
our understanding of the evolution of the outer solar system. While
ground
based compositional studies have hit their flux limits already
with
only a few objects sampled, we propose to exploit the new
capabilities
of WFC3 to perform the first ever large-scale
dynamical-compositional
study of Kuiper Belt Objects (KBOs) and their
progeny
to study the chemical, dynamical, and collisional history of the
region
of the giant planets. The sensitivity of the WFC3 observations
will
allow us to go up to two magnitudes deeper than our ground based
studies,
allowing us the capability of optimally selecting a target list
for
a large survey rather than simply taking the few objects that can be
measured,
as we have had to do to date. We have carefully constructed a
sample
of 120 objects which provides both overall breadth, for a general
understanding
of these objects, plus a large enough number of objects in
the
individual dynamical subclass to allow detailed comparison between
and
within these groups. These objects will likely define the core
Kuiper
Belt compositional sample for years to come. While we have many
specific
results anticipated to come from this survey, as with any
project
where the field is rich, our current knowledge level is low, and
a
new instrument suddenly appears which can exploit vastly larger
segments
of the population, the potential for discovery -- both
anticipated
and not -- is extraordinary.
WFC3/UVIS/IR
11909
UVIS
Hot Pixel Anneal
The
on-orbit radiation environment of WFC3 will continually generate new
hot
pixels. This proposal performs the procedure required for repairing
those
hot pixels in the UVIS CCDs. During an anneal, the two-stage
thermo-electric
cooler (TEC) is turned off and the four-stage TEC is
used
as a heater to bring the UVIS CCDs up to ~20 deg. C. As a result of
the
CCD warmup, a majority of the hot pixels will be fixed; previous
instruments
such as WFPC2 and ACS have seen repair rates of about 80%.
Internal
UVIS exposures are taken before and after each anneal, to allow
an
assessment of the procedure's effectiveness in WFC3, provide a check
of
bias, global dark current, and hot pixel levels, as well as support
hysteresis
(bowtie) monitoring and CDBS reference file generation. One
IR
dark is taken after each anneal, to provide a check of the IR
detector.