Daily Report #5075

HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #5075

PERIOD COVERED: 5am April 14 - 5am April 15, 2010 (DOY 104/09:00z-105/09:00z)

OBSERVATIONS SCHEDULED

ACS/WFC 11995

CCD Daily Monitor (Part 2)

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 320 orbits (20 weeks) from 1 February
2010 to 20 June 2010.

ACS/WFC/WFC3/IR 11802

WFC3/IR Observations of Strongly Lensing Clusters

We propose WFC3/IR observations of the massive lensing clusters Abell
1689 and Abell 1703 to constrain the properties of both cluster and
background field galaxies. The dataset will also help constrain the
photometric redshift of A1689-zD1, the bright galaxy candidate at
z~7.6.

NIC2/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.

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/MA2 11568

A SNAPSHOT Survey of the Local Interstellar Medium: New NUV
Observations of Stars with Archived FUV Observations

We propose to obtain high-resolution STIS E230H SNAP observations of
MgII and FeII interstellar absorption lines toward stars within 100
parsecs that already have moderate or high-resolution far-UV (FUV),
900-1700 A, observations available in the MAST Archive. Fundamental
properties, such as temperature, turbulence, ionization, abundances,
and depletions of gas in the local interstellar medium (LISM) can be
measured by coupling such observations. Due to the wide spectral range
of STIS, observations to study nearby stars also contain important
data about the LISM embedded within their spectra. However, unlocking
this information from the intrinsically broad and often saturated FUV
absorption lines of low-mass ions, (DI, CII, NI, OI), requires first
understanding the kinematic structure of the gas along the line of
sight. This can be achieved with high resolution spectra of high-mass
ions, (FeII, MgII), which have narrow absorption lines, and can
resolve each individual velocity component (interstellar cloud). By
obtaining short (~10 minute) E230H observations of FeII and MgII, for
stars that already have moderate or high- resolution FUV spectra, we
can increase the sample of LISM measurements, and thereby expand our
knowledge of the physical properties of the gas in our galactic
neighborhood. STIS is the only instrument capable of obtaining the
required high resolution data now or in the foreseeable future.

WFC3/ACS/IR 11584

Resolving the Smallest Galaxies with ACS

An order of magnitude more dwarf galaxies are expected to inhabit the
Local Group, based on currently accepted galaxy formation models, than
have been observed. This discrepancy has been noted in environments
ranging from the field to rich clusters, with evidence emerging that
lower density regions contain fewer dwarfs per giant than higher
density regions, in further contrast to model predictions. However,
there is no complete census of the faintest dwarf galaxies in any
environment. The discovery of the smallest and faintest dwarfs is
hampered by the limitations in detecting such compact or low surface
brightness galaxies, and this is compounded by the great difficulty in
determining accurate distances to, or ascertaining group membership
for, such faint objects. The M81 group provides a powerful means for
establishing membership for faint galaxies in a low density region.
With a distance modulus of 27.8, the tip of the red giant branch
(TRGB) appears at I ~ 24, just within the reach of ground based
surveys. We have completed a 65 square degree survey in the region
around M81 with the CFHT/MegaCam. Half of our survey was completed
before Cycle 16 and we were awarded time with WFPC2 to observe 15 new
candidate dwarf galaxy group members in F606W and F814W bands in order
to construct color-magnitude diagrams from which to measure accurate
TRGB distances and determine star formation and metallicity histories.
The data obtained show that 8 - 9 of these objects are galaxies at the
same distance as M81. In completing our survey, we have discovered an
additional 8 candidate galaxies we propose to image with ACS in order
to measure TRGB distances and establish membership. We also wish to
re-observe our smallest candidate group member and a tidal dwarf
candidate with deeper observations made possible with ACS. Once
membership has been established for this second set of candidates, we
will have a complete census of the dwarf galaxy population in the M8
group to M_r ~ -10, allowing us to obtain a firm measurement of the
luminosity function faint-end slope, and, combined with previous HST
data, to provide a complete inventory of the age and abundance
properties for the collapsed core of the M81 group.

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 11662

Improving the Radius-Luminosity Relationship for Broad-Lined AGNs with
a New Reverberation Sample

The radius-luminosity (R-L) relationship is currently the fundamental
basis for all techniques used to estimate black hole masses in AGNs,
in both the nearby and distant universe. However, the current R-L
relationship is based on 34 objects that cover a limited range in
black hole mass and luminosity. To improve our understanding of black
hole growth and evolution, the R-L relationship must be extended to
cover a broader range of black hole masses using the technique known
as reverberation mapping. To this end, we have been awarded an
unprecedented 64 nights on the Lick Observatory 3-m telescope between
March 24 and May 31, 2008, to spectroscopically monitor 12 AGNs in
order to measure their black hole masses. To properly determine the
luminosities of these 12 AGNs, we must correct them for their
host-galaxy starlight contributions using high-resolution images.
Previous work by Bentz et al. (2006) has shown that the starlight
correction to AGN luminosity measurements is an essential component to
interpreting the R-L relationship. The correction will be substantial
for each of the 12 sources we will monitor, as the AGNs are relatively
faint and embedded in nearby, bright galaxies. Starlight corrections
are not possible with ground-based images, as the PSF and bulge
contributions become indistinguishable under typical seeing
conditions, and adaptive optics are not yet operational in the
spectral range where the corrections are needed. In addition, spectral
decompositions are very model-dependent and are limited by the degree
of accuracy to which we understand emission processes and stellar
populations in galaxies. Without correcting for starlight, we will be
unable to apply the results of our Spring 2008 campaign to the body of
knowledge from previous reverberation mapping work. Therefore, we
propose to obtain high resolution, high dynamic range images of the
host galaxies of the 12 AGNs in our ground-based monitoring sample, as
well as one white dwarf which will be used as a PSF model.

STIS/CCD 11849

STIS CCD Hot Pixel Annealing

This purpose of this activity is to repair radiation induced hot pixel
damage to the STIS CCD by warming the CCD to the ambient instrument
temperature and annealing radiation damaged pixels. Radiation damage
creates hot pixels in the STIS CCD Detector. Many of these hot pixels
can be repaired by warming the CCD from its normal operating
temperature near -83 C to the ambient instrument temperature (~ +5 C)
for several hours. The number of hot pixels repaired is a function of
annealing temperature. The effectiveness of the CCD hot pixel
annealing process is assessed by measuring the dark current behavior
before and after annealing and by searching for any window
contamination effects.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

12247 - STIS CCD Dark Image Shifted One Column to the Left

The STIS Science Team has reported the one dark science image taken on
2010/003/13:37:00.000 for Proposal 11849 - STIS CCD Hot Pixel
Annealing.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSAcq 12 12
FGS REAcq 8 8
OBAD with Maneuver 6 6

SIGNIFICANT EVENTS: (None)