HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5032
PERIOD
COVERED: 5am February 11 - 5am February 12, 2010 (DOY 042/10:00z-043/10:00z)
OBSERVATIONS
SCHEDULED
COS/FUV
11997
FUV
Internal/External Wavelength Scale Monitor
This
program monitors the offsets between the wavelength scale set by
the
internal wavecal versus that defined by absorption lines in external
targets.
This is accomplished by observing two external targets in the
SMC:
SK191 with G130M and G160M and Cl* NGC 330 ROB B37 with G140L
(SK191
is too bright to be observed with G140L). The cenwaves observed
in
this program are a subset of the ones used during Cycle 17. Observing
all
cenwaves would require a considerably larger number of orbits.
Constraints
on scheduling of each target are placed so that each target
is
observed once every ~2-3 months. Observing the two targets every
month
would also require a considerably larger number of orbits.
STIS/CCD
11844
CCD
Dark Monitor Part 1
The
purpose of this proposal is to monitor the darks for the STIS CCD.
STIS/CCD
11846
CCD
Bias Monitor-Part 1
The
purpose of this proposal is to 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/ACS/IR
11563
Galaxies
at z~7-10 in the Reionization Epoch: Luminosity Functions to
<0.2L*
from Deep IR Imaging of the HUDF and HUDF05 Fields
The
first generations of galaxies were assembled around redshifts
z~7-10+,
just 500-800 Myr after recombination, in the heart of the
reionization
of the universe. We know very little about galaxies in this
period.
Despite great effort with HST and other telescopes, less than
~15
galaxies have been reliably detected so far at z>7, contrasting with
the
~1000 galaxies detected to date at z~6, just 200-400 Myr later, near
the
end of the reionization epoch. WFC3 IR can dramatically change this
situation,
enabling derivation of the galaxy luminosity function and its
shape
at z~7-8 to well below L*, measurement of the UV luminosity
density
at z~7-8 and z~8-9, and estimates of the contribution of
galaxies
to reionization at these epochs, as well as characterization of
their
properties (sizes, structure, colors). A quantitative leap in our
understanding
of early galaxies, and the timescales of their buildup,
requires
a total sample of ~100 galaxies at z~7-8 to ~29 AB mag. We can
achieve
this with 192 WFC3 IR orbits on three disjoint fields
(minimizing
cosmic variance): the HUDF and the two nearby deep fields of
the
HUDF05. Our program uses three WFC3 IR filters, and leverages over
600
orbits of existing ACS data, to identify, with low contamination, a
large
sample of over 100 objects at z~7-8, a very useful sample of ~23
at
z~8-9, and limits at z~10. By careful placement of the WFC3 IR and
parallel
ACS pointings, we also enhance the optical ACS imaging on the
HUDF
and a HUDF05 field. We stress (1) the need to go deep, which is
paramount
to define L*, the shape, and the slope alpha of the luminosity
function
(LF) at these high redshifts; and (2) the far superior
performance
of our strategy, compared with the use of strong lensing
clusters,
in detecting significant samples of faint z~7-8 galaxies to
derive
their luminosity function and UV ionizing flux. Our recent z~7.4
NICMOS
results show that wide-area IR surveys, even of GOODS-like depth,
simply
do not reach faint enough at z~7-9 to meet the LF and UV flux
objectives.
In the spirit of the HDF and the HUDF, we will waive any
proprietary
period, and will also deliver the reduced data to STScI. The
proposed
data will provide a Legacy resource of great value for a wide
range
of archival science investigations of galaxies at redshifts z~2-9.
The
data are likely to remain the deepest IR/optical images until JWST
is
launched, and will provide sources for spectroscopic followup by
JWST,
ALMA and EVLA.
WFC3/ACS/UVIS/IR
11570
Narrowing
in on the Hubble Constant and Dark Energy
A
measurement of the Hubble constant to a precision of a few percent
would
be a powerful aid to the investigation of the nature of dark
energy
and a potent "end-to end" test of the present cosmological model.
In
Cycle 15 we constructed a new streamlined distance ladder utilizing
high-
quality type Ia supernova data and observations of Cepheids with
HST
in the near-IR to minimize the dominant sources of systematic
uncertainty
in past measurements of the Hubble constant and reduce its
total
uncertainty to a little under 5%. Here we propose to exploit this
new
route to reduce the remaining uncertainty by more than 30%,
translating
into an equal reduction in the uncertainty of the equation
of
state of dark energy. We propose three sets of observations to reach
this
goal: a mosaic of NGC 4258 with WFC3 in F160W to triple its sample
of
long period Cepheids, WFC3/F160W observations of the 6 ideal SN Ia
hosts
to triple their samples of Cepheids, and observations of NGC 5584
the
host of a new SN Ia, SN 2007af, to discover and measure its Cepheids
and
begin expanding the small set of SN Ia luminosity calibrations.
These
observations would provide the bulk of a coordinated program aimed
at
making the measurement of the Hubble constant one of the leading
constraints
on dark energy.
WFC3/UV/S/C
12054
Generic
Offset Slew Correction Check
This
proposal is designed to verify that the GENSLEW safe target offset
capability
is properly positioning the spacecraft where desired in an
end-to-end
sense. This dataset will verify that the various calculation
and
coordinate transformations are correct from their specification
within
APT through to their execution on-orbit.
WFC3/UVI/IR
11557
The
Nature of Low-Ionization BAL QSOs
The
rare subclass of optically-selected QSOs known as low-ionization
broad
absorption line (LoBAL) QSOs show signs of high-velocity gas
outflows
and reddened continua indicative of dust obscuration. Recent
studies
show that galaxies hosting LoBAL QSOs tend to be ultraluminous
infrared
systems that are undergoing mergers, and that have dominant
young
(< 100 Myr) stellar populations. Such studies support the idea
that
LoBAL QSOs represent a short- lived phase early in the life of
QSOs,
when powerful AGN-driven winds are blowing away the dust and gas
surrounding
the QSO. If so, understanding LoBALs would be critical in
the
study of phenomena regulating black hole and galaxy evolution, such
as
AGN feedback and the early stages of nuclear accretion. These
results,
however, come from very small samples that may have serious
selection
biases. We are therefore taking a more aggressive approach by
conducting
a systematic multiwavelength study of a volume limited sample
of
LoBAL QSOs at 0.5 < z < 0.6 drawn from SDSS. We propose to image
their
host galaxies in two bands using WFC3/UVIS and WFC3/IR to study
the
morphologies for signs of recent tidal interactions and to map their
interaction
and star forming histories. We will thus determine whether
LoBAL
QSOs are truly exclusively found in young merging systems that are
likely
to be in the early stages of nuclear accretion.
WFC3/UVIS
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/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.
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS
For DOY 029 and 037:
12187
- OTA SE review of PTAS processing revealed that REAcq(2,1,1) at
2010/029:12:28:35 required multiple attempts to achieve Coarse
Track
Data Valid.
12188
- OTA SE review of PTAS processing revealed that REAcq(2,3,3) at
2010/037:10:30:43 required multiple attempts to achieve Coarse
Track
Data Valid.
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSAcq
08
08
FGS
REAcq
07
07
OBAD
with Maneuver 04 04
SIGNIFICANT
EVENTS: (None)