HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5120
PERIOD
COVERED: 5am June 17 - 5am June 18, 2010 (DOY 168/09:00z-169/09:00z)
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
6
6
FGS
REAcq
9
9
OBAD
with Maneuver 5
5
SIGNIFICANT
EVENTS: (None)
OBSERVATIONS
SCHEDULED:
ACS/WFC3
11593
Dynamical
Masses of the Coolest Brown Dwarfs
T
dwarfs are excellent laboratories to study the evolution and the
atmospheric
physics of both brown dwarfs and extrasolar planets. To
date,
only a single T dwarf binary has a dynamical mass determination,
and
more are sorely needed. The prospects of measuring more dynamical
masses
over the next decade are limited to 6 known short-period T dwarf
binaries.
We propose here to obtain Long-Term HST/ACS monitoring for the
3
of the 6 binaries which cannot be resolved with AO from the ground.
Upon
completion, our program will substantially increase the number of T
dwarf
dynamical mass measurements and thereby provide key benchmarks for
testing
theoretical models of ultracool objects.
COS/FUV
11686
The
Cosmological Impact of AGN Outflows: Measuring Absolute Abundances
and
Kinetic Luminosities
AGN
outflows are increasingly invoked as a major contributor to the
formation
and evolution of supermassive black holes, their host
galaxies,
the surrounding IGM, and cluster cooling flows. Our HST/COS
proposal
will determine reliable absolute chemical abundances in six AGN
outflows,
which influences several of the processes mentioned above. To
date
there is only one such determination, done by our team on Mrk 279
using
16 HST/STIS orbits and 100 ksec of FUSE time. The advent of COS
and
its high sensitivity allows us to choose among fainter objects at
redshifts
high enough to preclude the need for FUSE. This will allow us
to
determine the absolute abundances for six AGN (all fainter than Mrk
279)
using only 40 HST COS orbits. This will put abundances studies in
AGN
on a firm footing, an elusive goal for the past four decades. In
addition,
prior FUSE observations of four of these targets indicate that
it
is probable that the COS observations will detect troughs from
excited
levels of C III. These will allow us to measure the distances of
the
outflows and thereby determine their kinetic luminosity, a major
goal
in AGN feedback research.
11686( 7) - 25-Sep-2009 13:44:14 - [ 2]
We
will use our state of the art column density extraction methods and
velocity-dependent
photoionization models to determine the abundances
and
kinetic luminosity. Previous AGN outflow projects suffered from the
constraints
of deciding what science we could do using ONE of the
handful
of bright targets that were observable. With COS we can choose
the
best sample for our experiment. As an added bonus, most of the
spectral
range of our targets has not been observed previously, greatly
increasing
the discovery phase space.
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
COS/NUV/FUV
11698
The
Structure and Dynamics of Virgo's Multi-Phase Intracluster Medium
The
dynamical flows of the intracluster medium (ICM) are largely
unknown.
We propose to map the spatial and kinematic distribution of the
warm
ICM of the nearby Virgo cluster using the Cosmic Origins
Spectrograph.
15 sightlines at a range of impact parameters within the
virial
radius of the cluster (0.2 - 1.7 Mpc) will be probed for
Lyman-alpha
absorption and the data compared to blind HI, dust and x-ray
surveys
to create a multi-phase map of the cluster's ICM. Absorption
line
sightlines are commonly 40-100 kpc from a galaxy, allowing the flow
of
baryons between galaxies and the ICM to be assessed. The velocity
distribution
of the absorbers will be directly compared to simulations
and
used to constrain the turbulent motions of the ICM. This proposal
will
result in the first map of a cluster's warm ICM and provide
important
tests for our theoretical understanding of cluster formation
and
the treatment of gas cooling in cosmological simulations.
FGS
11704
The
Ages of Globular Clusters and the Population II Distance Scale
Globular
clusters are the oldest objects in the universe whose age can
be
accurately determined. The dominant error in globular cluster age
determinations
is the uncertain Population II distance scale. We propose
to
use FGS 1R to obtain parallaxes with an accuracy of 0.2
milliarcsecond
for 9 main sequence stars with [Fe/H] < -1.5. This will
determine
the absolute magnitude of these stars with accuracies of 0.04
to
0.06mag. This data will be used to determine the distance to 24
metal-poor
globular clusters using main sequence fitting. These
distances
(with errors of 0.05 mag) will be used to determine the ages
of
globular clusters using the luminosity of the subgiant branch as an
age
indicator. This will yield absolute ages with an accuracy of 5%,
about
a factor of two improvement over current estimates. Coupled with
existing
parallaxes for more metal-rich stars, we will be able to
accurately
determine the age for globular clusters over a wide range of
metallicities
in order to study the early formation history of the Milky
Way
and provide an independent estimate of the age of the universe.
The
Hipparcos database contains only 1 star with [Fe/H] < -1.4 and an
absolute
magnitude error less than 0.18 mag which is suitable for use in
main
sequence fitting. Previous attempts at main sequence fitting to
metal-poor
globular clusters have had to rely on theoretical
calibrations
of the color of the main sequence. Our HST parallax program
will
remove this source of possible systematic error and yield distances
to
metal-poor globular clusters which are significantly more accurate
than
possible with the current parallax data. The HST parallax data will
have
errors which are 10 times smaller than the current parallax data.
Using
the HST parallaxes, we will obtain main sequence fitting distances
to
11 globular clusters which contain over 500 RR Lyrae stars. This will
allow
us to calibrate the absolute magnitude of RR Lyrae stars, a
commonly
used Population II distance indicator.
S/C
12046
COS
FUV DCE Memory Dump
Whenever
the FUV detector high voltage is on, count rate and current
draw
information is collected, monitored, and saved to DCE memory. Every
10
msec the detector samples the currents from the HV power supplies
(HVIA,
HVIB) and the AUX power supply (AUXI). The last 1000 samples are
saved
in memory, along with a histogram of the number of occurrences of
each
current value.
In
the case of a HV transient (known as a "crackle" on FUSE), where one
of
these currents exceeds a preset threshold for a persistence time, the
HV
will shut down, and the DCE memory will be dumped and examined as
part
of the recovery procedure. However, if the current exceeds the
threshold
for less than the persistence time (a "mini-crackle" in FUSE
parlance),
there is no way to know without dumping DCE memory. By
dumping
and examining the histograms regularly, we will be able to
monitor
any changes in the rate of "mini-crackles" and thus learn
something
about the state of the detector.
STIS/CC
11845
CCD
Dark Monitor Part 2
Monitor
the darks for the STIS CCD.
STIS/CC
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.
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
11915
IR
Internal Flat Fields
This
program is the same as 11433 (SMOV) and depends on the completion
of
the IR initial alignment (Program 11425). This version contains three
instances
of 37 internal orbits: to be scheduled early, middle, and near
the
end of Cycle 17, in order to use the entire 110-orbit allocation.
In
this test, we will study the stability and structure of the IR
channel
flat field images through all filter elements in the WFC3-IR
channel.
Flats will be monitored, i.e. to capture any temporal trends in
the
flat fields and delta flats produced. High signal observations will
provide
a map of the pixel-to-pixel flat field structure, as well as
identify
the positions of any dust particles.
WFC3/IR/S/C
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).
WFC3/UVIS
11714
Snapshot
Survey for Planetary Nebulae in Local Group Globular Clusters
Planetary
nebulae (PNe) in globular clusters (GCs) raise a number of
interesting
issues related to stellar and galactic evolution. The number
of
PNe known in Milky Way GCs, four, is surprisingly low if one assumes
that
all stars pass through a PN stage. However, it is likely that the
remnants
of stars now evolving in galactic GCs leave the AGB so slowly
that
any ejected nebula dissipates long before the star becomes hot
enough
to ionize it. Thus there should not be ANY PNe in Milky Way
GCs--but
there are four! It has been suggested that these Pne are the
result
of mergers of binary stars within GCs, i.e., that they are
descendants
of blue stragglers. The frequency of occurrence of PNe in
external
galaxies poses more questions, because it shows a range of
almost
an order of magnitude.
I
propose a SNAPshot survey aimed at discovering PNe in the GC systems
of
Local Group galaxies outside the Milky Way. These clusters, some of
which
may be much younger than their counterparts in our galaxy, might
contain
many more PNe than those of our own galaxy. I will use the
standard
technique of emission-line and continuum imaging, which easily
discloses
PNe. This proposal continues a WFPC2 program started in Cycle
16,
but with the more powerful WFC3. As a by-product, the survey will
also
produce color-magnitude diagrams for numerous clusters for the
first
time, reaching down to the horizontal branch.
WFC3/UVIS
11732
The
Temperature Profiles of Quasar Accretion Disks
We
can now routinely measure the size of quasar accretion disks using
gravitational
microlensing of lensed quasars. At optical wavelengths we
observe
a size and scaling with black hole mass roughly consistent with
thin
disk theory but the sizes are larger than expected from the
observed
optical fluxes. One solution would be to use a flatter
temperature
profile, which we can study by measuring the wavelength
dependence
of the disk size over the largest possible wavelength
baseline.
Thus, to understand the size discrepancy and to probe closer
to
the inner edge of the disk we need to extend our measurements to UV
wavelengths,
and this can only be done with HST. For example, in the UV
we
should see significant changes in the optical/UV size ratio with
black
hole mass. We propose monitoring 5 lenses spanning a broad range
of
black hole masses with well-sampled ground based light curves,
optical
disk size measurements and known GALEX UV fluxes during Cycles
17
and 18 to expand from our current sample of two lenses. We would
obtain
5 observations of each target in each Cycle, similar to our
successful
strategy for the first two targets.
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
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.
WFC3/UVIS
11912
UVIS
Internal Flats
This
proposal will be used to assess the stability of the flat field
structure
for the UVIS detector throughout the 15 months of Cycle 17.
The
data will be used to generate on-orbit updates for the delta-flat
field
reference files used in the WFC3 calibration pipeline, if
significant
changes in the flat structure are seen.