Notice: Due to the conversion of some ACS WFC or HRC observations into

WFPC2, or NICMOS observations after the loss of ACS CCD science

capability in January, there may be an occasional discrepancy between a

proposal's listed (and correct) instrument usage and the abstract that

follows it.

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT       # 4489

PERIOD COVERED: UT November 14, 2007 (DOY 318)

OBSERVATIONS SCHEDULED

ACS/SBC WFPC2 11175

UV Imaging to Determine the Location of Residual Star Formation in

Galaxies Recently Arrived on the Red Sequence

We have identified a sample of low-redshift {z = 0.04 - 0.10} galaxies

that are candidates for recent arrival on the red sequence. They have

red optical colors indicative of old stellar populations, but blue

UV-optical colors that could indicate the presence of a small quantity

of continuing or very recent star formation. However, their spectra lack

the emission lines that characterize star-forming galaxies. We propose

to use ACS/SBC to obtain high- resolution imaging of the UV flux in

these galaxies, in order to determine the spatial distribution of the

last episode of star formation. WFPC2 imaging will provide B, V, and I

photometry to measure the main stellar light distribution of the galaxy

for comparison with the UV imaging, as well as to measure color

gradients and the distribution of interstellar dust. This detailed

morphological information will allow us to investigate the hypothesis

that these galaxies have recently stopped forming stars and to compare

the observed distribution of the last star formation with predictions

for several different mechanisms that may quench star formation in

galaxies.

WFPC2 10766

A Deep X-ray Survey of the Small Magellanic Cloud

We request deep observations of 2 representative fields in the Small

Magellanic Cloud with Chandra and HST, with the primary goal of measuring

the luminosity function and space density of X-ray binaries and other

sources down to an unprecedented faint luminosity limit of 2x10E32

erg/s. This will be the faintest XLF ever obtained for any galaxy,

including our own. HST photometry to 24th magnitude in V and I filters

will identify the sources and provide Fx/Fopt, which will be vital in

quantifying the LMXB population and in measuring the properties of the

first coronally active stars ever detected in an external galaxy.

NIC1/NIC2 11204

Imaging Circumstellar Disks and Envelopes around Proto-Brown Dwarfs

Using the Spitzer Space Telescope, we have discovered two young brown

dwarfs with Class I spectral energy distributions {i.e., proto-brown

dwarfs}. We propose to perform broad-band NICMOS imaging of these Class

I brown dwarfs to spatially resolve their circumstellar disks and

envelopes. If successful, these data would comprise the first

measurements of this kind for brown dwarfs and would provide fundamental

constraints on models for the formation of brown dwarfs.

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration - CR Persistence Part 5

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 DARKs. 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.

S/C 11163

Accreting Pulsating White Dwarfs in Cataclysmic Variables

Recent ground-based observations have increased the number of known

pulsating white dwarfs in close binaries with active mass transfer

{cataclysmic variables} from 5 to 11 systems. Our past Cycles 8 and 11

STIS observations of the first 2 known, followed by our Cycle 13 SBC

observations of the next 3 discovered, revealed the clear presence of

the white dwarf and increased amplitude of the pulsations in the UV

compared to the optical. The temperatures derived from the UV spectra

show 4 systems are much hotter than non- interacting pulsating white

dwarfs. A larger sample is needed to sort out the nature of the

instability strip in accreting pulsators i.e. whether effects of

composition and rotation due to accretion result in a well-defined

instability strip as a function of Teff.

WFPC2 11103

A Snapshot Survey of The Most Massive Clusters of Galaxies

We propose the continuation of our highly successful SNAPshot survey of

a sample of 125 very X-ray luminous clusters in the redshift range

0.3-0.7. As demonstrated by the 25 snapshots obtained so far in Cycle14

and Cycle15 these systems frequently exhibit strong gravitational

lensing as well as spectacular examples of violent galaxy interactions.

The proposed observations will provide important constraints on the

cluster mass distributions, the physical nature of galaxy-galaxy and

galaxy-gas interactions in cluster cores, and a set of optically bright,

lensed galaxies for further 8-10m spectroscopy. All of our primary

science goals require only the detection and characterization of

high-surface-brightness features and are thus achievable even at the

reduced sensitivity of WFPC2. Because of their high redshift and thus

compact angular scale our target clusters are less adversely affected by

the smaller field of view of WFPC2 than more nearby systems.

Acknowledging the broad community interest in this sample we waive our

data rights for these observations. Due to a clerical error at STScI our

approved Cycle15 SNAP program was barred from execution for 3 months and

only 6 observations have been performed to date - reinstating this SNAP

at Cycle16 priority is of paramount importance to reach meaningful

statistics.

WFPC2 11178

Probing Solar System History with Orbits, Masses, and Colors of

Transneptunian Binaries

The recent discovery of numerous transneptunian binaries {TNBs} opens a

window into dynamical conditions in the protoplanetary disk where they

formed as well as the history of subsequent events which sculpted the

outer Solar System and emplaced them onto their present day heliocentric

orbits. To date, at least 47 TNBs have been discovered, but only about a

dozen have had their mutual orbits and separate colors determined,

frustrating their use to investigate numerous important scientific

questions. The current shortage of data especially cripples scientific

investigations requiring statistical comparisons among the ensemble

characteristics. We propose to obtain sufficient astrometry and

photometry of 23 TNBs to compute their mutual orbits and system masses

and to determine separate primary and secondary colors, roughly tripling

the sample for which this information is known, as well as extending it

to include systems of two near-equal size bodies. To make the most

efficient possible use of HST, we will use a Monte Carlo technique to

optimally schedule our observations.

WFPC2 11202

The Structure of Early-type Galaxies: 0.1-100 Effective Radii

The structure, formation and evolution of early-type galaxies is still

largely an open problem in cosmology: how does the Universe evolve from

large linear scales dominated by dark matter to the highly non-linear

scales of galaxies, where baryons and dark matter both play important,

interacting, roles? To understand the complex physical processes

involved in their formation scenario, and why they have the tight

scaling relations that we observe today {e.g. the Fundamental Plane}, it

is critically important not only to understand their stellar structure,

but also their dark-matter distribution from the smallest to the largest

scales. Over the last three years the SLACS collaboration has developed

a toolbox to tackle these issues in a unique and encompassing way by

combining new non-parametric strong lensing techniques, stellar

dynamics, and most recently weak gravitational lensing, with

high-quality Hubble Space Telescope imaging and VLT/Keck spectroscopic

data of early-type lens systems. This allows us to break degeneracies

that are inherent to each of these techniques separately and probe the

mass structure of early-type galaxies from 0.1 to 100 effective radii.

The large dynamic range to which lensing is sensitive allows us both to

probe the clumpy substructure of these galaxies, as well as their

low-density outer haloes. These methods have convincingly been

demonstrated, by our team, using smaller pilot-samples of SLACS lens

systems with HST data. In this proposal, we request observing time with

WFPC2 and NICMOS to observe 53 strong lens systems from SLACS, to obtain

complete multi-color imaging for each system. This would bring the total

number of SLACS lens systems to 87 with completed HST imaging and

effectively doubles the known number of galaxy-scale strong lenses. The

deep HST images enable us to fully exploit our new techniques, beat down

low-number statistics, and probe the structure and evolution of

early-type galaxies, not only with a uniform data-set an order of

magnitude larger than what is available now, but also with a fully

coherent and self-consistent methodological approach!

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               06                 06                                     

FGS REacq               08                 08  

OBAD with Maneuver 28                 28                                      

SIGNIFICANT EVENTS:

Flash Report: Bay 8 Hot Season Plan Briefing

The Bay 8 Hot Season Planning briefing was held on Tuesday November 13,

2007. During this season there are two beta peaks that are of concern.

The first peak is at the end of November and the second is in January.

The 2007/2008 peaks are not expected to reach as high as the 2006/2007

season. HST Project approved the plan to not impose a hard attitude

restriction but to have the STScI review the Bay 8 incidence angles

during the peak times and make adjustments as necessary.