Daily Rpt #4977

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #4977

PERIOD COVERED: 5am November 20 - 5am November 23, 2009 (DOY 324/10:00z-327/10:00z)

OBSERVATIONS SCHEDULED

WFC3/IR 11930

IR Gain Measurement

The gain of the IR channel of WFC3 will be measured using a series of
internal flat fields. Using knowledge gained from ground testing, we
propose to collect flat field ramps which will be used to create
photon transfer curves and give a measure of the gain. By using two
filters centered at similar wavelengths but differing bandwidths, we
will be able to search for any flux- dependent changes in the measure
of the gain.

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/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/UV 11918

WFC3 UVIS Image Quality

The UVIS imaging performance over the detector will be assessed
periodically (every 4 months) in two passbands (F275W and F621M) to
check for image stability. The field around star 58 in the open
cluster NGC188 is the chosen target because it is sufficiently dense
to provide good sampling over the FOV while providing enough isolated
stars to permit accurate PSF (point spread function) measurement. It
is available year-round and used previously for ACS image quality
assessment. The field is astrometric, and astrometric guide stars will
be used, so that the plate scale and image orientation may also be
determined if necessary (as in SMOV proposals 11436 and 11442). Full
frame images will be obtained at each of 4 POSTARG offset positions
designed to improve sampling over the detector.

This proposal is a periodic repeat (once every 4 months) of visits
similar to those in SMOV proposal 11436 (activity ID WFC3-23). The
data will be analyzed using the code and techniques described in ISR
WFC3 2008-40 (Hartig). Profiles of encircled energy will be monitored
and presented in an ISR. If an update to the SIAF is needed, (V2, V3)
locations of stars will be obtained from the Flight Ops Sensors and
Calibrations group at GSFC, the (V2, V3) of the reference pixel and
the orientation of the detector will be determined by the WFC3 group,
and the Telescopes group will update and deliver the SIAF to the PRDB
branch.

The specific PSF metrics to be examined are encircled energy for
aperture diameter 0.15, 0.20, 0.25, and 0.35 arcsec, FWHM, and
sharpness. (See ISR WFC3 2008-40 tables 2 and 3 and preceding text.)
about 20 stars distributed over the detector will be measured in each
exposure for each filter. The mean, rms, and rms of the mean will be
determined for each metric. The values determined from each of the 4
exposures per filter within a visit will be compared to each other to
see to what extent they are affected by "breathing". Values will be
compared from visit to visit, starting with the values obtained during
SMOV after the fine alignment has been performed, to see if the
measures of the compactness of the PSF indicate degradation over time.
The analysis will be repeated for stars on the inner part of the
detector and stars on the outer part of the detector to check for
differential degradation of the PSF.

As an example of the analysis, one can examine the sharpness of the
F275W PSF exposures made during thermal vacuum testing (ISR WFC3
2008-40). To compare two samples, one can define the PSFs on each CCD
chip as a sample of 8. The mean, rms, and rms of the mean sharpness
are 0.0676, 0.0093, and 0.0035 for one chip, and 0.0701, 0.0085, and
0.0032 for the other. The difference of the means is 0.0025 and the
statistical error in that difference is 0.0048, so the difference is
not significant.

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 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).

ACS/WFC 11879

CCD Daily Monitor (Part 1)

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 352 orbits (22 weeks) from 31 August
2009 to 31 January 2010.

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.

STIS/CCD 11844

CCD Dark Monitor Part 1

The purpose of this proposal is to monitor the darks for the STIS CCD.

STIS/CCD 11740

A Complete Optical and NIR Atmospheric Transmission Spectrum of the
Exoplanet HD189733b

The hot Jupiter HD189733b offers the best exoplanet in which to
perform atmospheric studies through transit spectroscopy. Here we
propose STIS and NICMOS spectra to help construct a full exoplanetary
transit transmission spectrum that extends over the entire optical and
near-infrared range. Such a spectrum will link existing observed
atmospheric features such as haze, water, and methane, providing a
coherent understanding of all these reported features. With a spectrum
covering many observed absorption features, the absolute pressure
scale and abundances can be determined linking observed features to
the actual atmospheric properties of the exoplanet.

WFC3/UV/ACS/WFC 11724

Direct Age Determination of the Local Group dE Galaxies NGC 147 and
NGC 185

The origin of dwarf elliptical (dE) galaxies remains a mystery and the
dE galaxies of the Local Group provide the best opportunity to study
this galaxy class in detail. We propose to obtain ACS photometry of
main sequence turnoff stars in the M31 dE satellites NGC 147 and NGC
185. Because these galaxies have little to no stars younger than 1
Gyr, resolving the main sequence turnoff is required to directly
quantify their star formation histories. NGC 147 and NGC 185 are the
only two dEs for which a clean measurement is feasible with the HST.
This proposal was accepted in Cycle 15, but little data were taken
before the failure of ACS. The main sequence turnoffs of NGC 147 and
NGC 185 are expected to be at an apparent magnitude of V=29; we
request F606W/F814W imaging one half magnitude fainter than this limit
(three magnitudes fainter than the deepest previous dE observations).
Quantifying the ratio of old to intermediate-age stars will allow us
to discriminate between competing models of dE formation. On-going
Keck/DEIMOS spectroscopy of several hundred red giant stars in each of
these two dE galaxies, coupled with dynamical modeling and spectral
synthesis, will complement the ACS measurement by providing
information on chemical abundance patterns, dark matter content and
internal dynamics. The proposed ACS data will be the first to directly
quantify the onset and duration of star formation episodes in dE
galaxies, and will thereby form the cornerstone in what promises to be
the most comprehensive study of this class of galaxies.

WFC3/IR 11666

Chilly Pairs: A Search for the Latest-type Brown Dwarf Binaries and
the Prototype Y Dwarf

We propose to use HST/NICMOS to image a sample of 27 of the nearest (
20 pc) and lowest luminosity T-type brown dwarfs in order to identify
and characterize new very low mass binary systems. Only 3 late-type T
dwarf binaries have been found to date, despite that fact that these
systems are critical benchmarks for evolutionary and atmospheric
models at the lowest masses. They are also the most likely systems to
harbor Y dwarf companions, an as yet unpopulated putative class of
very cold (T 600 K) brown dwarfs. Our proposed program will more
than double the number of T5-T9 dwarfs imaged at high resolution, with
an anticipated yield of ~5 new binaries with initial characterization
of component spectral types. We will be able to probe separations
sufficient to identify systems suitable for astrometric orbit and
dynamical mass measurements. We also expect one of our discoveries to
contain the first Y-type brown dwarf. Our proposed program complements
and augments ongoing ground-based adaptive optics surveys and provides
pathway science for JWST.

WFC3/UVIS 11588

Galaxy-Scale Strong Lenses from the CFHTLS Survey

We aim to investigate the origin and evolution of early-type galaxies
using gravitational lensing, modeling the mass profiles of objects
over a wide range of redshifts. The low redshift (z = 0.2) sample is
already in place following the successful HST SLACS survey; we now
propose to build up and analyze a sample of comparable size (~50
systems) at high redshift (0.4 z 0.9) using HST WFC3 Snapshot
observations of lens systems identified by the SL2S collaboration in
the CFHT legacy survey.

WFC3/UVIS 11565

A Search for Astrometric Companions to Very Low-Mass, Population II
Stars

We propose to carry out a Snapshot search for astrometric companions
in a subsample of very low-mass, halo subdwarfs identified within 120
parsecs of the Sun. These ultra-cool M subdwarfs are local
representatives of the lowest-mass H burning objects from the Galactic
Population II. The expected 3-4 astrometric doubles that will be
discovered will be invaluable in that they will be the first systems
from which gravitational masses of metal-poor stars at the bottom of
the main sequence can be directly measured.

WFC3/IR 11548

Infrared Imaging of Protostars in the Orion A Cloud: The Role of
Environment in Star Formation

We propose NICMOS and WFC3/IR observations of a sample of 252
protostars identified in the Orion A cloud with the Spitzer Space
Telescope. These observations will image the scattered light escaping
the protostellar envelopes, providing information on the shapes of
outflow cavities, the inclinations of the protostars, and the overall
morphologies of the envelopes. In addition, we ask for Spitzer time to
obtain 55-95 micron spectra of 75 of the protostars. Combining these
new data with existing 3.6 to 70 micron photometry and forthcoming
5-40 micron spectra measured with the Spitzer Space Telescope, we will
determine the physical properties of the protostars such as envelope
density, luminosity, infall rate, and outflow cavity opening angle. By
examining how these properties vary with stellar density (i.e.
clusters vs. groups vs. isolation) and the properties of the
surrounding molecular cloud; we can directly measure how the
surrounding environment influences protostellar evolution, and
consequently, the formation of stars and planetary systems.
Ultimately, this data will guide the development of a theory of
protostellar evolution.

WFC3/IR 11166

The Mass-dependent Evolution of the Black Hole-Bulge Relations

In the local universe, the masses of giant black holes are correlated
with the luminosities, masses and velocity dispersions of their host
galaxy bulges. This indicates a surprisingly close connection between
the evolution of galactic nuclei (on parsec scales) and of stars on
kpc scales. A key observational test of proposed explanations for
these correlations is to measure how they have evolved over cosmic
time. Our ACS imaging of 20 Seyfert 1 galaxies at z=0.37 showed them
to have smaller bulges (by a factor of 3) for a given central black
hole mass than is found in galaxies in the present-day universe.
However, since all our sample galaxies had black hole masses in the
range 10^8.0--8.5 Msun, we could only measure the OFFSET in black hole
mass to bulge luminosity ratios from the present epoch. By extending
this study to black hole masses another factor of 10 lower, we propose
to determine the full CORRELATION of black hole mass with host galaxy
properties at a lookback time of 4 Gyrs and to test mass-dependency of
the evolution. We have selected 14 Seyfert galaxies from SDSS DR5
whose narrow Hbeta emission lines (and estimated nuclear luminosities)
imply that they have black hole masses around 10^7 Msuns. We will soon
complete our Keck spectroscopic measures of their bulge velocity
dispersions. We need a 1-orbit NICMOS image of each galaxy to separate
its nonstellar luminosity from its bulge and disk. This will allow us
to make the first determination of the full black hole/bulge relations
at z=0.37 (e.g. M-L and M-sigma), as well as a test of whether active
galaxies obey the Fundamental Plane relation at that epoch.

WFC3/IR 11150

Beta Pic Polarimetry with NICMOS

Debris disk stars host transient dust grains that comprise a
collisional cascade with sizes ranging from planetesimals to the
sub-micron. In addition to the gravity of the host star and any
planets present, these grains are subject to size-dependent
non-gravitational forces, e.g., corpuscular drag and radiation
pressure. When a steep spectrum of grain sizes prevails, such as the
Dohnanyi distribution, scattered light images preferentially trace
grains with dimensionless size parameter of order unity. Thus images
in scattered starlight provide unique windows on the balance of forces
acting on grains at a specific size. Therefore, in an A star system
such as beta Pic, the near-IR is dominated by grains close to the blow
out size and therefore NICMOS traces dust on hyperbolic orbits.

Scattering is fundamentally polarization sensitive, and measurements
that record intensity literally see only half the picture. If linear
polarization is measured then the elements of the complex scattering
matrix can be reconstructed. These matrix elements provide fundamental
constraints on the size, composition and structure of the scatterers.
Notably, polarimetry can be used to break the degeneracy between
scattering asymmetry, g, and the radial dust gradient, which are
otherwise covariant in an edge-on disk. Thus, we can use polarimetry
to localize the parent bodies in the beta Pic disk.

In beta Pic, dust is thought to originate mainly from the sublimation
of cometary bodies near periastron. The irradiation of cometary
material leads to sublimation and photodissociation of ices forming
porous grains consisting of a matrix of refractory material. Such
grains have a characteristic scattering signature in polarized light
that can be distinguished from compact grains that arise from
collisional erosion of asteroidal material.

WFC3/ACS/IR/WFC 11142

Revealing the Physical Nature of Infrared Luminous Galaxies at
0.3z2.7 Using HST and Spitzer

We aim to determine physical properties of IR luminous galaxies at
0.3z2.7 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
(0.3z2.7). 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 0.3z2.7, and establish
if major mergers are the drivers of z1 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, and (3) obtain the current best estimates of the far-IR
emission, thus L(bol) for this sample, and establish if the relative
contribution of mid-to-far IR dust emission is correlated with
morphology (resolved vs. unresolved).

WFPC3/IR 11099

A "silver bullet" for the sources of reionization

Recent discoveries of z6 galaxies have given us the first glimpse of
the Universe shortly after the era of reionization. The questions
arose whether these first galaxies can be made responsible for the
reionization process, and how long did it last. Neither observations
nor theory provide a clean answer. In particular observations give
results that are barely mutually consistent and need to be further
tested. Observing high redshift (z7) sources is in general difficult,
mostly due to the high luminosity distance to these objects, and
partly due to the lower expected stellar masses compared to objects at
moderate redshifts.

We propose to use one of the most massive, merging cluster 1E0657-56
(z=0.295) as a cosmic telescopes to efficiently probe the
high-redshift universe. The gravitational potential well of this
cluster provides several magnitudes of magnification, enabling study
of intrinsically lower luminosity galaxies.As we discuss in the
proposal, due to its highly elongated mass distribution and ideal
redshift the bullet cluster is a prime candidate for this study. We
propose deep NICMOS and WFPC2 observations; with much reduced
observing time compared to e.g. NICMOS UDF we expect an order of
magnitude more (~5 candidates) z7 objects. They will also likely be
multiply imaged, and since the geometry of images depends upon the
redshift, we will be able to confirm their nature, thereby not
requiring (often prohibitive at these magnitudes) spectroscopic
follow-up. This will enable us to count high-redshift sources and
constrain their luminosity function; a task made possible with the
help of gravitational lensing even in the pre-JWST era.

STIS/CCD 10897

Coronagraphic imaging of the submillimeter debris disk of a 200Myr old
M-dwarf

A recent sub-millimeter survey has unambiguously discovered a new
debris disk around the M0.5 dwarf GJ842.2 which is 200 Myr old.
Reanalysis of the IRAS data has shown that there is also a 25 micron
excess toward this star indicating warm dust close to the star. It is
also only the second debris disk found among M-dwarfs that constitute
70 % of the stars in the Galaxy. Collisional and Poynting-Roberston
timescale arguments indicate that the cold grains detected in the
sub-mm are ``primordial'', i.e. original grains from the
protoplanetary phase. The disk around GJ842.2 is thus unique in terms
of the presence of dust at such a late stage of evolution and presents
two conundrums: why did it retain so much primordial dust at large
distances, and why does it continue to produce dust close to the star?
We propose to conduct high contrast NICMOS coronagraphic imaging of
GJ842.2 to determine the spatial distribution of the small reflecting
grains and test the various scenarios which might explain the IRAS and
sub-mm data e.g. resonant trapping of dust by planets or
"sandblasting'' by interstellar medium grains working more
aggressively on a low-luminosity star than on an A-type star like Beta
Pic. Also, we would search for an evolutionary sequence between
GJ842.2 and the only other M-dwarf with a disk resolved by HST, the 10
Myr old AU Mic system.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS: (None)

#12085 GSAcq(1,2,1) scheduled at 324/18:22:51z failed due search
radius limit exceeded on FGS1 during LOS @324/18:29z

Observations affected: WFC3 #164-165 Proposal #11166

#12086 GSAcq(1,2,1) resulted in Fine Lock Backup (2,0,2) @325/17:49z

Observations possibly affected: WFC3 #235, 2 & 3 Proposal #11588

#12091 GSAcq(2,1,1) @326/07:55z failed to Fine Lock Backup on FGS2
during LOS

Observations possibly affected: ACS #66 Proposal #11724

#12094 GSAcq(1,2,1) failed @ 326/20:37z, and REAcq(1,2,1) failed
@326/22:01z, due to Search Radius Limit Exceeded on FGS-1

Observations affected: STIS #55 Proposal #10897

COMPLETED OPS REQUEST:

#18562-1 CONTINGENCY: Continuous FGS Loss of Lock looping (Generic)
@326/20:52z

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSAcq 21 19
FGS REAcq 22 21
OBAD with Maneuver 11 11

SIGNIFICANT EVENTS: (None)