Daily Report # 4417

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***** # 4417

PERIOD COVERED: UT August 1, 2007 (DOY 213)

OBSERVATIONS SCHEDULED

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 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.

NIC2 11208

The co-evolution of spheroids and black holes in the last six billion
years

The masses of giant black holes are correlated with the luminosities,
masses, and velocity dispersions of the bulges of their host galaxies.
This empirical correlation of phenomena on widely different scales
{from pcs to kpcs} suggests that the formation and evolution of
galaxies and central black holes are closely linked. In Cycle 13, we
have started a campaign to map directly the co-evolution of spheroids
and black-holes by measuring in observationally favorable redshift
windows the empirical correlations connecting their properties. By
focusing on Seyfert 1s, where the nucleus and the stars contribute
comparable fractions of total light, black hole mass and bulge
dispersion are obtained from Keck spectroscopy. HST is required for
accurate measurement of the non stellar AGN continuum, the morphology
of the galaxy, and the structural parameters of the bulge. The results
at z=0.36 indicate a surprisingly fast evolution of bulges in the past
4 Gyrs {significant at the 95%CL}, in the sense that bulges were
significantly smaller for a given black hole mass. Also, the large
fraction of mergers and disturbed galaxies {4+2 out of 20} identifies
gas-rich mergers as the mechanisms responsible for bulge-growth. Going
to higher redshift -- where evolutionary trends should be stronger --
is needed to confirm these tantalizing results. We propose therefore
to push our investigation to the next suitable redshift window z=0.57
{lookback-time 6 Gyrs}. Fifteen objects are the minimum number
required to map the evolution of the empirical correlations between
bulge properties and black-hole mass, and to achieve a conclusive
detection of evolution {99%CL}.

WFPC2 11027

Visible Earth Flats

This proposal monitors flatfield stability. This proposal obtains
sequences of Earth streak flats to construct high quality flat fields
for the WFPC2 filter set. These flat fields will allow mapping of the
OTA illumination pattern and will be used in conjuction with previous
internal and external flats to generate new pipeline superflats. These
Earth flats will complement the Earth flat data obtained during cycles
4-14.

WFPC2 11029

WFPC2 CYCLE 15 Intflat Linearity Check and Filter Rotation Anomaly
Monitor

Intflat observations will be taken to provide a linearity check: the
linearity test consists of a series of intflats in F555W, in each gain
and each shutter. A combination of intflats, visflats, and earthflats
will be used to check the repeatability of filter wheel motions.
{Intflat sequences tied to decons, visits 1-18 in prop 10363, have
been moved to the cycle 15 decon proposal xxxx for easier scheduling.}
Note: long-exposure WFPC2 intflats must be scheduled during ACS
anneals to prevent stray light from the WFPC2 lamps from contaminating
long ACS external exposures.

WFPC2 11084

Probing the Least Luminous Galaxies in the Local Universe

We propose to obtain deep color-magnitude data of eight new Local
Group galaxies which we recently discovered: Andromeda XI, Andromeda
XII, and Andromeda XIII {satellites of M31}; Canes Venatici I, Canes
Venatici II, Hercules, and Leo IV {satellites of the Milky Way}; and
Leo T, a new "free-floating" Local Group dwarf spheroidal with
evidence for recent star formation and associated H I gas. These
represent the least luminous galaxies known at *any* redshift, and are
the only accessible laboratories for studying this extreme regime of
galaxy formation. With deep WFPC-2 F606W and F814W pointings at their
centers, we will determine whether these objects contain single or
multiple age stellar populations, as well as whether these objects
display a range of metallicities.

WFPC2 11100

Two new `bullets' for MOND: revealing the properties of dark matter in
massive merging clusters

The principal objective of this proposal is to study the physical
nature of dark matter by using two, massive, newly-identified merging
clusters of galaxies. As shown by the pioneering example of the
``bullet cluster'' {1E0657-56}, such systems are ideal laboratories
for detecting dark matter and distinguishing between cold dark matter
{CDM} and other scenarios {e.g. self- interacting dark matter}. Our
limit on the self-interaction cross-section of dark matter relies on
the assumption of a normal pre-merger mass-to-light ratios, and a
small impact parameter during the collision of the two clusters. In
order to mitigate any possible systematic effects, it is vital to
extend this work to other, similar systems. With detailed observations
of new systems, the systematic uncertainties in the dark matter cross
section calculations can be improved substantially, allowing us to
move from rough order of magnitude estimates to measurements with
quantifiable uncertainties that can be compared usefully with the
predictions from numerical simulations. Our targets are two
extraordinary, high-redshift, merging galaxy clusters recently
discovered by the Massive Cluster Survey {MACS}. This survey is by far
the best matched to this study, since it selects medium redshift
{optimal for gravitational lensing studies} and X-ray luminous {hence
massive} objects. We have selected the best candidates with clear
evidence for considerable offsets between the hot X-ray emitting gas
and optically luminous stellar material. The two most striking
examples are the targets of this proposal. To pin down the position of
the dark matter component we require high resolution, absolutely
calibrated mass maps. The combination of weak and strong lensing
measurements is needed to attain this goal. This can only be achieved
with the excellent resolving power of the HST {in combination with
wide-field, multicolor Subaru data already in hand}. We therefore
request multicolor HST/WFPC2 observations of the two merging clusters.
The combination of constraints from multiply lensed images {identified
via morphology and color information} and high-resolution weak lensing
data will allow us to construct, self-consistently, their mass
distribution from the very centers to the outskirts. Gravitational
lensing thus provides a unique tool transforming these clusters into
dark matter laboratories. They will supply us with answers as to the
nature and properties of dark matter, and how it shapes galaxies and
galaxy clusters and their evolution through cosmic time.

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 undertstand 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 seperately and probe the mass structure of early-type
galaxies from 0.1 to 100 effective radii. The large dynamic range to
which lensing is sentive 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!

WFPC2/NIC3 11188

First Resolved Imaging of Escaping Lyman Continuum

The emission from star-forming galaxies appears to be responsible for
reionization of the universe at z6. However, the models that attempt
to describe the detailed impact of high- redshift galaxies on the
surrounding inter-galactic medium {IGM} are strongly dependent upon
several uncertain parameters. Perhaps the most uncertain is the
fraction of HI-ionizing photons produced by young stars which escape
into the IGM. Most attempts to measure this "escape fraction" {f_esc}
have produced null results. Recently, a small subset of z~3 Lyman
Break Galaxies {LBGs} has been found exhibiting large escape
fractions. It remains unclear however, what differentiates them from
other LBGs. Several models attempt to explain how such a large
fraction of ionizing continuum can escape through the HI and dust in
the ISM {eg. "chimneys" created by SNe winds, globular cluster
formation, etc.}, each producing unique signatures which can be
observed with resolved imaging of the escaping Lyman continuum. We
propose a deep, high resolution WFPC2 image of the ionizing continuum
{F336W} and the rest-frame 1500 Angstrom continuum {F606W} of five of
the six known LBGs with large escape fractions. These LBGs all fit
within a single WFPC2 pointing, yielding high observing efficiency.
Additionally, they all have z~3.1 or higher, the optimal redshift
range for probing the Lyman Continuum region with available WFPC2
filters. These factors make our proposed sample especially suitable
for follow- up. With these data we will discern the mechanisms
responsible for producing large escape fractions, and therefore gain
insight into the process of reionization.

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************** 07**************** 07
FGS REacq************** 08**************** 08
OBAD with Maneuver **** 30**************** 30

SIGNIFICANT EVENTS: (None)