Daily #4007

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT #4007

PERIOD COVERED: UT December 13, 2005 (DOY 347)

OBSERVATIONS SCHEDULED

ACS/HRC 10738

Earth Flats

Sky flats will be obtained by observing the bright Earth with the HRC
and WFC. These observations will be used to verify the accuracy of the
flats currently in the pipeline and to monitor any changes. Weekly
coronagraphic monitoring is required to assess the changing position
of the spots.

ACS/WFC 10496

Decelerating and Dustfree: Efficient Dark Energy Studies with
Supernovae and Clusters

We propose a novel HST approach to obtain a dramatically more useful
"dust free" Type Ia supernovae {SNe Ia} dataset than available with
the previous GOODS searches. Moreover, this approach provides a
strikingly more efficient search-and-follow-up that is primarily pre-
scheduled. The resulting dark energy measurements do not share the
major systematic uncertainty at these redshifts, that of the
extinction correction with a prior. By targeting massive galaxy
clusters at z 1 we obtain a five-times higher efficiency in
detection of Type Ia supernovae in ellipticals, providing a
well-understood host galaxy environment. These same deep cluster
images then also yield fundamental calibrations required for future
weak lensing and Sunyaev-Zel'dovich measurements of dark energy, as
well as an entire program of cluster studies. The data will make
possible a factor of two improvement on supernova constraints on dark
energy time variation, and much larger improvement in systematic
uncertainty. They will provide both a cluster dataset and a SN Ia
dataset that will be a longstanding scientific resource.

ACS/WFC 10509

The Cluster Lens SDSS 1004+4112: Constraining World Models With its
Multiply-Imaged Quasar and

We will use deep ACS imaging of the giant {15 arcsec} four-image
z_s=1.734 lensed quasar SDSS 1004+4112, and its z_l=0.68 lensing
galaxy cluster, to identify many additional multiply- imaged
background galaxies. Combining the existing single orbit ACS I-band
image with ground based data, we have definitely identified two
multiply imaged galaxies with estimated redshifts of 2.6 and 4.3,
about 15 probable images of background galaxies, and a point source in
the core of the central cD galaxy, which is likely to be the faint,
fifth image of the quasar. The new data will provide accurate
photometric redshifts, confirm that the candidate fifth image has the
same spectral energy distribution as the other quasar images, allow
secure identification of additional multiply-lensed galaxies for
improving the mass model, and permit identification of faint cluster
members. Due to the high lens redshift and the broad redshift
distribution of the lensed background sources, we should be able to
use the source-redshift scaling of the Einstein radius that depends on
{d_ls/d_os}, to derive a direct, geometric estimate of Omega_Lambda.
The deeper images will also allow a weak lensing analysis to extend
the mass distribution to larger radii. Unlike any other cluster
lenses, the time delay between the lensed quasar images {already
measured for the A--B images, and measurable for the others over the
next few years}, breaks the so-called kappa-degeneracies that
complicate weak-lensing analyses.

ACS/WFC 10522

Calibrating Star Formation: The Link between Feedback and Galaxy
Evolution

Stellar feedback - the return of mass and energy from star formation
to the interstellar medium - is one of the primary engines of galaxy
evolution. Yet, the theoretical foundation of mechanical feedback is,
to date, unconstrained by observations. We propose to investigate this
fundamental aspect of star formation on a sample of two local actively
star-forming galaxies, NGC4449, and Holmberg II. The two galaxies have
been selected to occupy an unexplored, yet crucial for quantifying
mechanical feedback, niche in the two-parameter space of star
formation intensity and galaxy mass. ACS/WFC and WFPC2 narrow-band
observations in the light of H-beta, [OIII], H-alpha, and [NII] will
be obtained for both galaxies, in order to: {1} discriminate the
feedback- induced shock fronts from the photoionization regions; {2}
map the shocks inside and around the starburst regions; and {3}
measure the energy budget of the star-formation-produced shocks. These
observations, complemented by existing data, will yield: {1} the
efficiency of the feedback, i.e. the fraction of the star formation's
mechanical energy that is transported out of the starburst volume
rather than confined or radiated away; {2} the dependence of this
efficiency on the two fundamental parameters of star formation
intensity and stellar mass. The high angular resolution of HST is
crucial for separating the spatially narrow shock fronts {~5 pc,
~0.25" at 4 Mpc} from the more extended photoionization fronts. The
legacy from this project will be the most complete quantitative
measurement of the energetics associated with feedback processes. We
will secure the first milestone for placing feedback mechanisms on a
solid physical ground, and for understanding quantitatively their role
on the energetics, structure, and star formation history of galaxies
at all redshifts.

ACS/WFC/NIC3/WFPC2 10530

Probing Evolution And Reionization Spectroscopically {PEARS}

While imaging with HST has gone deep enough to probe the highest
redshifts, e.g. the GOODS survey and the Ultra Deep Field,
spectroscopic identifications have not kept up. We propose an ACS
grism survey to get slitless spectra of all sources in a wide survey
region {8 ACS fields} up to z =27.0 magnitude, and an ultradeep field
in the HUDF reaching sources up to z =28 magnitude. The PEARS survey
will: {1} Find and spectrocopically confirm all galaxies between
z=4-7. {2} Probe the reionization epoch by robustly determining the
luminosity function of galaxies and low luminosity AGNs at z = 4 - 6.
With known redshifts, we can get a local measure of star formation and
ionization rate in case reionization is inhomogeneous. {3} Study
galaxy formation and evolution by finding galaxies in a contiguous
redshift range between 4 z 7, and black hole evolution through a
census of low-luminosity AGNs. {4} Get a robust census of galaxies
with old stellar populations at 1 z 2.5, invaluable for checking
consistency with heirarchical models of galaxy formation. Fitting
these galaxies' spectra will yield age and metallicity estimates. {5}
Study star-formation and galaxy assembly at its peak at 1 z 2 by
identifying emission lines in star-forming galaxies, old populations
showing the 4000A break, and any combination of the two. {6} Constrain
faint white dwarfs in the Galactic halo and thus measure their
contribution to the dark matter halo. {7} Derive spectro-photometric
redshifts by using the grism spectra along with broadband data. This
will be the deepest unbiased spectroscopy yet, and will enhance the
value of the multiwavelength data in UDF and the GOODS fields to the
astronomical community. To this end we will deliver reduced spectra to
the HST archives.

NICMOS 8791

NICMOS Post-SAA calibration - CR Persistence Part 2

A new procedure proposed to alleviate the CR-persistence problem of
NICMOS. Dark frames will be obtained immediately upon exiting the SAA
contour 23, and every time a NICMOS exposure is scheduled within 50
minutes of coming out of the SAA. The darks will be obtained in
parallel in all three NICMOS Cameras. The POST-SAA darks will be
non-standard reference files available to users with a USEAFTER
date/time mark. The keyword 'USEAFTER=date/time' will also be added to
the header of each POST-SAA DARK frame. The keyword must be populated
with the time, in addition to the date, because HST crosses the SAA ~8
times per day so each POST-SAA DARK will need to have the appropriate
time specified, for users to identify the ones they need. Both the raw
and processed images will be archived as POST-SAA DARKSs. Generally we
expect that all NICMOS science/calibration observations started within
50 minutes of leaving an SAA will need such maps to remove the CR
persistence from the science images. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

WFPC2 10745

WFPC2 CYCLE 14 INTERNAL MONITOR

This calibration proposal is the Cycle 14 routine internal monitor for
WFPC2, to be run weekly to monitor the health of the cameras. A
variety of internal exposures are obtained in order to provide a
monitor of the integrity of the CCD camera electronics in both bays
{both gain 7 and gain 15 -- to test stability of gains and bias
levels}, a test for quantum efficiency in the CCDs, and a monitor for
possible buildup of contaminants on the CCD windows. These also
provide raw data for generating annual super-bias reference files for
the calibration pipeline.

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 08 08
FGS REacq 06 06
OBAD with Maneuver 24 24

SIGNIFICANT EVENTS: (None)