HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5146
PERIOD
COVERED: 5am July 26 - 5am July 27, 2010 (DOY 207/09:00z-208/09:00z)
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
8
8
FGS
REAcq
9
9
OBAD
with Maneuver 5
5
SIGNIFICANT
EVENTS: (None)
OBSERVATIONS
SCHEDULED:
ACS/WFC
11996
CCD
Daily Monitor (Part 3)
This
program comprises basic tests for measuring the read noise and dark
current
of the ACS WFC and for tracking the growth of hot pixels. The
recorded
frames are used to create bias and dark reference images for
science
data reduction and calibration. This program will be executed
four
days per week (Mon, Wed, Fri, Sun) for the duration of Cycle 17. To
facilitate
scheduling, this program is split into three proposals. This
proposal
covers 308 orbits (19.25 weeks) from 21 June 2010 to 1 November
2010.
COS/FUV
11895
FUV
Detector Dark Monitor
Monitor
the FUV detector dark rate by taking long science exposures
without
illuminating 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/FUV/STIS/CCD/MA1
11592
Testing
the Origin(s) of the Highly Ionized High-Velocity Clouds: A
Survey
of Galactic Halo Stars at z>3 kpc
Cosmological
simulation predicts that highly ionized gas plays an
important
role in the formation and evolution of galaxies and their
interplay
with the intergalactic medium. The NASA HST and FUSE missions
have
revealed high-velocity CIV and OVI absorption along extragalactic
sightlines
through the Galactic halo. These highly ionized high-velocity
clouds
(HVCs) could cover 85% of the sky and have a detection rate
higher
than the HI HVCs. Two competing, equally exciting, theories may
explain
the origin of these highly ionized HVCs: 1) the "Galactic"
theory,
where the HVCs are the result of feedback processes and trace
the
disk-halo mass exchange, perhaps including the accretion of matter
condensing
from an extended corona; 2) the "Local Group" theory, where
they
are part of the local warm-hot intergalactic medium, representing
some
of the missing baryonic matter of the Universe. Only direct
distance
determinations can discriminate between these models. Our group
has
found that some of these highly ionized HVCs have a Galactic origin,
based
on STIS observations of one star at z<5.3 kpc. We propose an HST
FUV
spectral survey to search for and characterize the high velocity NV,
CIV,
and SiIV interstellar absorption toward 24 stars at much larger
distances
than any previous searches (4<d<21 kpc, 3<|z|<13 kpc). COS
will
provide atomic to highly ionized species (e.g.,OI, CII, CIV, SiIV)
that
can be observed at sufficient resolution (R~22, 000) to not only
detect
these highly ionized HVCs but also to model their properties and
understand
their physics and origins. This survey is only possible
because
of the high sensitivity of COS in the FUV spectral range.
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
11896
NUV
Spectroscopic Sensitivity Monitoring
The
purpose of this proposal is to monitor sensitivity of each NUV
grating
mode to detect any changes due to contamination or other causes.
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.
STIS/CCD
11721
Verifying
the Utility of Type Ia Supernovae as Cosmological Probes:
Evolution
and Dispersion in the Ultraviolet Spectra
The
study of distant type Ia supernova (SNe Ia) offers the most
practical
and immediate discriminator between popular models of dark
energy.
Yet fundamental questions remain over possible
redshift-dependent
trends in their observed and intrinsic properties.
High-quality
Keck spectroscopy of a representative sample of 36
intermediate
redshift SNe Ia has revealed a surprising, and unexplained,
diversity
in their rest-frame UV fluxes. One possible explanation is
hitherto
undiscovered variations in the progenitor metallicity.
Unfortunately,
this result cannot be compared to local UV data as only
two
representative SNe Ia have been studied near maximum light. Taking
advantage
of two new `rolling searches' and the restoration of STIS, we
propose
a non-disruptive TOO campaign to create an equivalent comparison
local
sample. This will allow us to address possible evolution in the
mean
UV spectrum and its diversity, an essential precursor to the study
of
SNe beyond z~1.
STIS/CCD
11852
STIS
CCD Spectroscopic Flats C17
The
purpose of this proposal is to obtain pixel-to-pixel lamp flat
fields
for the STIS CCD in spectroscopic mode.
WFC3/UV/ACS/WFC/IR
12055
A
Panchromatic Hubble Andromeda Treasury - I
We
propose to image the north east quadrant of M31 to deep limits in the
UV,
optical, and near-IR. HST imaging should resolve the galaxy into
more
than 100 million stars, all with common distances and foreground
extinctions.
UV through NIR stellar photometry (F275W, F336W with
WFC3/UVIS,
F475W and F814W with ACS/WFC, and F110W and F160W with
WFC3/NIR)
will provide effective temperatures for a wide range of
spectral
types, while simultaneously mapping M31's extinction. Our
central
science drivers are to: understand high-mass variations in the
stellar
IMF as a function of SFR intensity and metallicity; capture the
spatially-resolved
star formation history of M31; study a vast sample of
stellar
clusters with a range of ages and metallicities. These are
central
to understanding stellar evolution and clustered star formation;
constraining
ISM energetics; and understanding the counterparts and
environments
of transient objects (novae, SNe, variable stars, x-ray
sources,
etc.). As its legacy, this survey adds M31 to the Milky Way and
Magellanic
Clouds as a fundamental calibrator of stellar evolution and
star-formation
processes for understanding the stellar populations of
distant
galaxies. Effective exposure times are 977s in F275W, 1368s in
F336W,
4040s in F475W, 4042s in F814W, 699s in F110W, and 1796s in
F160W,
including short exposures to avoid saturation of bright sources.
These
depths will produce photon-limited images in the UV. Images will
be
crowding-limited in the optical and NIR, but will reach below the red
clump
at all radii. The images will reach the Nyquist sampling limit in
F160W,
F475W, and F814W.
WFC3/UVIS
11707
Detecting
Isolated Black Holes through Astrometric Microlensing
This
proposal aims to make the first detection of isolated stellar-mass
black
holes (BHs) in the Milky Way, and to determine their masses. Until
now,
the only directly measured BH masses have come from radial-velocity
measurements
of X-ray binaries. Our proposed method uses the astrometric
shifts
that occur when a galactic-bulge microlensing event is caused by
a
BH lens. Out of the hundreds of bulge microlensing events found
annually
by the OGLE and MOA surveys, a few are found to have very long
durations
(>200 days). It is generally believed that the majority of
these
long-duration events are caused by lenses that are isolated BHs.
To
test this hypothesis, we will carry out high-precision astrometry of
5
long-duration events, using the ACS/HRC camera. The expected
astrometric
signal from a BH lens is >1.4 mas, at least 7 times the
demonstrated
astrometric precision attainable with the HRC.
This
proposal will thus potentially lead to the first unambiguous
detection
of isolated stellar-mass BHs, and the first direct mass
measurement
for isolated stellar-mass BHs through any technique.
Detection
of several BHs will provide information on the frequency of
BHs
in the galaxy, with implications for the slope of the IMF at high
masses,
the minimum mass of progenitors that produce BHs, and
constraints
on theoretical models of BH formation.
WFC3/UVIS
11903
UVIS
Photometric Zero Points
This
proposal obtains the photometric zero points in 53 of the 62
UVIS/WFC3
filters: the 18 broad-band filters, 8 medium-band filters, 16
narrow-band
filters, and 11 of the 20 quad filters (those being used in
cycle
17). The observations will be primary obtained by observing the
hot
DA white dwarf standards GD153 and G191-B2B. A redder secondary
standard,
P330E, will be observed in a subset of the filters to provide
color
corrections. Repeat observations in 16 of the most widely used
cycle
17 filters will be obtained once per month for the first three
months,
and then once every second month for the duration of cycle 17,
alternating
and depending on target availability. These observations
will
enable monitoring of the stability of the photometric system.
Photometric
transformation equations will be calculated by comparing the
photometry
of stars in two globular clusters, 47 Tuc and NGC 2419, to
previous
measurements with other telescopes/instruments.
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).