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Daily Report #4513



 
 
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Old December 26th 07, 04:33 PM posted to sci.astro.hubble
Cooper, Joe
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Posts: 568
Default Daily Report #4513

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT***** # 4513

PERIOD COVERED: UT December 21,22,23,24,25, 2007 (DOY
355,356,357,358,359)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA calibration - CR Persistence Part 6

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.

NIC1/NIC2/NIC3 11330

NICMOS Cycle 16 Extended Dark

This takes a series of Darks in parallel to other instruments.

ACS/SBC 11220

Mapping the FUV Evolution of Type IIn Supernovae

We will use the PR110L prism on the SBC of ACS to map the FUV
evolution of Type IIn supernovae {SNe}. The main goal of this proposal
is to measure the FUV continuum, Ly-a emission line flux, and their
evolution to {1} quantify and interpret Type IIn SN transient event
detections at high redshift and {2} dramatically improve current high
redshift Type IIn selection criteria. We show that the inherent
properties of Type IIn SNe facilitate high redshift detection. We will
observe the rest-frame FUV of a sample of eight 0.02 z 0.33 Type
IIn SNe to directly measure the survival of Ly-alpha photons in low to
intermediate redshift Type IIn SNe environments and extrapolate the
results to high redshift. We will calibrate relationships such as FUV
luminosity vs. emission line flux and measure emission line evolution
vs. FUV light evolution. The intent is to categorize and improve the
utility of Type IIn SNe.

NIC2 11219

Active Galactic Nuclei in nearby galaxies: a new view of the origin of
the radio-loud radio- quiet dichotomy?

Using archival HST and Chandra observations of 34 nearby early-type
galaxies {drawn from a complete radio selected sample} we have found
evidence that the radio-loud/radio-quiet dichotomy is directly
connected to the structure of the inner regions of their host galaxies
in the following sense: [1] Radio-loud AGN are associated with
galaxies with shallow cores in their light profiles [2] Radio-quiet
AGN are only hosted by galaxies with steep cusps. Since the brightness
profile is determined by the galaxy's evolution, through its merger
history, our results suggest that the same process sets the AGN
flavour. This provides us with a novel tool to explore the
co-evolution of galaxies and supermassive black holes, and it opens a
new path to understand the origin of the radio-loud/radio-quiet AGN
dichotomy. Currently our analysis is statistically incomplete as the
brightness profile is not available for 82 of the 116 targets. Most
galaxies were not observed with HST, while in some cases the study is
obstructed by the presence of dust features. We here propose to
perform an infrared NICMOS snapshot survey of these 82 galaxies. This
will enable us to i} test the reality of the dichotomic behaviour in a
substantially larger sample; ii} extend the comparison between
radio-loud and radio-quiet AGN to a larger range of luminosities.

FGS 11211

An Astrometric Calibration of Population II Distance Indicators

In 2002 HST produced a highly precise parallax for RR Lyrae. That
measurement resulted in an absolute magnitude, M{V}= 0.61+/-0.11, a
useful result, judged by the over ten refereed citations each year
since. It is, however, unsatisfactory to have the direct,
parallax-based, distance scale of Population II variables based on a
single star. We propose, therefore, to obtain the parallaxes of four
additional RR Lyrae stars and two Population II Cepheids, or W Vir
stars. The Population II Cepheids lie with the RR Lyrae stars on a
common K-band Period-Luminosity relation. Using these parallaxes to
inform that relationship, we anticipate a zero-point error of 0.04
magnitude. This result should greatly strengthen confidence in the
Population II distance scale and increase our understanding of RR
Lyrae star and Pop II Cepheid astrophysics.

NIC3 11195

Morphologies of the Most Extreme High-Redshift Mid-IR-luminous
Galaxies II: The `Bump' Sources

The formative phase of some of the most massive galaxies may be
extremely luminous, characterized by intense star- and AGN-formation.
Till now, few such galaxies have been unambiguously identified at high
redshift, and thus far we have been restricted to studying the
low-redshift ultraluminous infrared galaxies as possible analogs. We
have recently discovered a sample of objects which may indeed
represent this early phase in galaxy formation, and are undertaking an
extensive multiwavelength study of this population. These objects are
optically extremely faint {R26} but nevertheless bright at
mid-infrared wavelengths {F[24um] 0.5 mJy}. Mid-infrared
spectroscopy with Spitzer/IRS reveals that they have redshifts z~2,
implying luminosities ~1E13 Lsun. Their mid-IR SEDs fall into two
broad, perhaps overlapping, categories. Sources with brighter F[24um]
exhibit power-law SEDs and SiO absorption features in their mid-IR
spectra characteristic of AGN, whereas those with fainter F[24um] show
a "bump" characteristic of the redshifted 1.6um peak from a stellar
population, and PAH emission characteristic of starformation. We have
begun obtaining HST images of the brighter sources in Cycle 15 to
obtain identifications and determine kpc-scale morphologies for these
galaxies. Here, we aim to target the second class {the "bump" sources}
with the goal of determining if these constitute morphologically
different objects, or simply a "low-AGN" state of the brighter class.
The proposed observations will help us determine whether these objects
are merging systems, massive obscured starbursts {with obscuration on
kpc scales!} or very reddened {locally obscured} AGN hosted by
intrinsically low-luminosity galaxies.

WFPC2 11187

A Deep Search for Martian Dust Rings

It has been long suspected that Mars is encircled by two faint rings
of dust, one originating from each of its moons Phobos and Deimos.
Similar dust rings are associated with many of the small, inner moons
orbiting Jupiter, Saturn, Uranus and Neptune. On December 31, 2007,
Earth will pass through Mars' equatorial plane just a week after its
December 24 opposition, providing an exceedingly rare opportunity to
image the rings under nearly ideal viewing geometry. The next
equivalent viewing opportunity occurs in 2022. Using the Wide Fields
of WFPC2 and a highly optimized observing plan, we expect to be able
to detect rings with edge-on reflectivities of ~ 10^-8, which is at or
below the level where most dynamicists expect rings to be visible.
This is a factor of 10-30 more sensitive than the detection limit we
achieved during a slightly inferior viewing opportunity in 2001. The
rings have been predicted to show some interesting dynamical
properties, including large asymmetries and inclinations. A positive
detection will test these predictions, serving as an effective test of
dynamical models developed to account for the properties of other
faint planetary rings as well. With such a stringent limit, even a
negative result will be of considerable interest, challenging
dynamicists to explain the remarkably low density of dust within the
Martian system.

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 11176

Location and the Origin of Short Gamma-Ray Bursts

During the past decade extraordinary progress has been made in
determining the origin of long-duration gamma-ray bursts. It has been
conclusively shown that these objects derive from the deaths of
massive stars. Nonetheless, the origin of their observational cousins,
short-duration gamma-ray bursts {SGRBs} remains a mystery. While SGRBs
are widely thought to result from the inspiral of compact binaries,
this is a conjecture. A number of hosts of SGRBs have been identified,
and have been used by some to argue that SGRBs derive primarily from
an ancient population {~ 5 Gyr}; however, it is not known whether this
conclusion more accurately reflects selection biases or astrophysics.
Here we propose to employ a variant of a technique that we pioneered
and used to great effect in elucidating the origins of long-duration
bursts. We will examine the degree to which SGRB locations trace the
red or blue light of their hosts, and thus old or young stellar
populations. This approach will allow us to study the demographics of
the SGRB population in a manner largely free of the distance dependent
selection effects which have so far bedeviled this field, and should
give direct insight into the age of the SGRB progenitor population.

NC3 11165

The Radius of the "Super-Neptune" HD 149026b

Current measurements suggest that the transiting exoplanet HD 149026b
is a "super- Neptune," with an enormous heavy-element core. The
existence of such a planet is a major challenge to planet formation
theories. We propose to place the radius measurement on much firmer
footing, by obtaining a NICMOS light curve with 0.4 mmag precision and
13 sec cadence. We will improve the radius measurement by a factor of
2.3, and more importantly, the result will be more robust because we
will determine the stellar radius directly from the data. Numerous
attempts to do this from the ground have failed.

NIC2 11155

Dust Grain Evolution in Herbig Ae Stars: NICMOS Coronagraphic Imaging
and Polarimetry

We propose to take advantage of the sensitive coronagraphic
capabilities of NICMOS to obtain multiwavelength coronagraphic imaging
and polarimetry of primordial dust disks around young
intermediate-mass stars {Herbig Ae stars}, in order to advance our
understanding of how dust grains are assembled into larger bodies.
Because the polarization of scattered light is strongly dependent on
scattering particle size and composition, coronagraphic imaging
polarimetry with NICMOS provides a uniquely powerful tool for
measuring grain properties in spatially resolved circumstellar disks.
It is widely believed that planets form via the gradual accretion of
planetesimals in gas-rich, dusty circumstellar disks, but the
connection between this suspected process and the circumstellar disks
that we can now observe around other stars remains very uncertain. Our
proposed observations, together with powerful 3-D radiative transfer
codes, will enable us to quantitatively determine dust grain
properties as a function of location within disks, and thus to test
whether dust grains around young stars are in fact growing in size
during the putative planet-formation epoch. HST imaging polarimetry of
Herbig Ae stars will complement and extend existing polarimetric
studies of disks around lower-mass T Tauri stars and debris disks
around older main-sequence stars. When combined with these previous
studies, the proposed research will help us establish the influence of
stellar mass on the growth of dust grains into larger planetesimals,
and ultimately to planets. Our results will also let us calibrate
models of the thermal emission from these disks, a critical need for
validating the properties of more distant disks inferred on the basis
of spectral information alone.

WFPC2/NIC3 11144

Building on the Significant NICMOS Investment in GOODS: A Bright,
Wide-Area Search for z=7 Galaxies

One of the most exciting frontiers in observational cosmology has been
to trace the buildup and evolution of galaxies from very early times.
While hierarchical theory teaches us that the star formation rate in
galaxies likely starts out small and builds up gradually, only
recently has it been possible to see evidence for this observationally
through the evolution of the LF from z~6 to z~3. Establishing that
this build up occurs from even earlier times {z~7-8} has been
difficult, however, due to the small size of current high-redshift
z~7-8 samples -- now numbering in the range of ~4-10 sources.
Expanding the size of these samples is absolutely essential, if we are
to push current studies of galaxy buildup back to even earlier times.
Fortunately, we should soon be able to do so, thanks to ~50 arcmin**2
of deep {26.9 AB mag at 5 sigma} NICMOS 1.6 micron data that will be
available over the two ACS GOODS fields as a result of one recent
180-orbit ACS backup program and a smaller program. These data will
nearly triple the deep near-IR imaging currently available and
represent a significant resource for finding and characterizing the
brightest high-redshift sources -- since high-redshift candidates can
be easily identified in these data from their red z-H colours.
Unfortunately, the red z-H colours of these candidates are not
sufficient to determine that these sources are at z=7, and it is
important also to have deep photometry at 1.1 microns. To obtain this
crucial information, we propose to follow up each of these z- H
dropouts with NICMOS at 1.1 microns to determine which are at high
redshift and thus significantly expand our sample of luminous, z=7
galaxies. Since preliminary studies indicate that these candidates
occur in only 30% of the NIC3 fields, our follow-up strategy is ~3
times as efficient as without this preselection and 9 times as
efficient as a search in a field with no pre-existing data. In total,
we expect to identify ~8 luminous z-dropouts and possibly ~2 z~10
J-dropouts as a result of this program, more than tripling the number
currently known. The increased sample sizes are important if we are to
solidify current conclusions about galaxy buildup and the evolution of
the LF from z~8. In addition to the high redshift science, these deep
1.1 micron data would have significant value for many diverse
endeavors, including {1} improving our constraints on the stellar mass
density at z~7-10 and {2} doubling the number of galaxies at z~6 for
which we can estimate dust obscuration.

WFPC2 11130

AGNs with Intermediate-mass Black Holes: Testing the Black Hole-Bulge
Paradigm, Part II

The recent progress in the study of central black holes in galactic
nuclei has led to a general consensus that supermassive {10^6-10^9
solar mass} black holes are closely connected with the formation and
evolutionary history of large galaxies, especially their bulge
component. Two outstanding issues, however, remain unresolved. Can
central black holes form in the absence of a bulge? And does the mass
function of central black holes extend below 10^6 solar masses?
Intermediate-mass black holes {10^6 solar masses}, if they exist, may
offer important clues to the nature of the seeds of supermassive black
holes. Using the SDSS, our group has successfully uncovered a new
population of AGNs with intermediate-mass black holes that reside in
low-luminosity galaxies. However, very little is known about the
detailed morphologies or structural parameters of the host galaxies
themselves, including the crucial question of whether they have bulges
or not. Surprisingly, the majority of the targets of our Cycle 14
pilot program have structural properties similar to dwarf elliptical
galaxies. The statistics from this initial study, however, are really
too sparse to reach definitive conclusions on this important new class
of black holes. We wish to extend this study to a larger sample, by
using the Snapshot mode to obtain WFPC2 F814W images from a parent
sample of 175 AGNs with intermediate-mass black holes selected from
our final SDSS search. We are particularly keen to determine whether
the hosts contain bulges, and if so, how the fundamental plane
properties of the host depend on the mass of their central black
holes. We will also investigate the environment of this unique class
of AGNs.

WFPC2 11113

Binaries in the Kuiper Belt: Probes of Solar System Formation and
Evolution

The discovery of binaries in the Kuiper Belt and related small body
populations is powering a revolutionary step forward in the study of
this remote region. Three quarters of the known binaries in the Kuiper
Belt have been discovered with HST, most by our snapshot surveys. The
statistics derived from this work are beginning to yield surprising
and unexpected results. We have found a strong concentration of
binaries among low-inclination Classicals, a possible size cutoff to
binaries among the Centaurs, an apparent preference for nearly equal
mass binaries, and a strong increase in the number of binaries at
small separations. We propose to continue this successful program in
Cycle 16; we expect to discover at least 13 new binary systems,
targeted to subgroups where these discoveries can have the greatest
impact.

NIC3 11107

Imaging of Local Lyman Break Galaxy Analogs: New Clues to Galaxy
Formation in the Early Universe

We have used the ultraviolet all-sky imaging survey currently being
conducted by the Galaxy Evolution Explorer {GALEX} to identify for the
first time a rare population of low- redshift starbursts with
properties remarkably similar to high-redshift Lyman Break Galaxies
{LBGs}. These "compact UV luminous galaxies" {UVLGs} resemble LBGs in
terms of size, SFR, surface brightness, mass, metallicity, kinematics,
dust, and color. The UVLG sample offers the unique opportunity of
investigating some very important properties of LBGs that have
remained virtually inaccessible at high redshift: their morphology and
the mechanism that drives their star formation. Therefore, in Cycle 15
we have imaged 7 UVLGs using ACS in order to 1} characterize their
morphology and look for signs of interactions and mergers, and 2}
probe their star formation histories over a variety of timescales. The
images show a striking trend of small-scale mergers turning large
amounts of gas into vigorous starbursts {a process referred to as
dissipational or "wet" merging}. Here, we propose to complete our
sample of 31 LBG analogs using the ACS/SBC F150LP {FUV} and WFPC2
F606W {R} filters in order to create a statistical sample to study the
mechanism that triggers star formation in UVLGs and its implications
for the nature of LBGs. Specifically, we will 1} study the trend
between galaxy merging and SFR in UVLGs, 2} artificially redshift the
FUV images to z=1-4 and compare morphologies with those in similarly
sized samples of LBGs at the same rest-frame wavelengths in e.g.
GOODS, UDF, and COSMOS, 3} determine the presence and morphology of
significant stellar mass in "pre-burst" stars, and 4} study their
immediate environment. Together with our Spitzer {IRAC+MIPS}, GALEX,
SDSS and radio data, the HST observations will form a unique union of
data that may for the first time shed light on how the earliest major
episodes of star formation in high redshift galaxies came about. This
proposal was adapted from an ACS HRC+WFC proposal to meet the new
Cycle 16 observing constraints, and can be carried out using the
ACS/SBC and WFPC2 without compromising our original science goals.

NIC3 11080

Exploring the Scaling Laws of Star Formation

As a variety of surveys of the local and distant Universe are
approaching a full census of galaxy populations, our attention needs
to turn towards understanding and quantifying the physical mechanisms
that trigger and regulate the large-scale star formation rates {SFRs}
in galaxies.

WFPC2 11079

Treasury Imaging of Star Forming Regions in the Local Group:
Complementing the GALEX and NOAO Surveys

We propose to use WFPC2 to image the most interesting star-forming
regions in the Local Group galaxies, to resolve their young stellar
populations. We will use a set of filters including F170W, which is
critical to detect and characterize the most massive stars, to whose
hot temperatures colors at longer wavelengths are not sensitive.
WFPC2's field of view ideally matches the typical size of the
star-forming regions, and its spatial resolution allows us to measure
individual stars, given the proximity of these galaxies. The resulting
H-R diagrams will enable studies of star-formation properties in these
regions, which cover largely differing metallicities {a factor of 17,
compared to the factor of 4 explored so far} and characteristics. The
results will further our understanding of the star-formation process,
of the interplay between massive stars and environment, the properties
of dust, and will provide the key to interpret integrated measurements
of star-formation indicators {UV, IR, Halpha} available for several
hundreds more distant galaxies. Our recent deep surveys of these
galaxies with GALEX {FUV, NUV} and ground-based imaging {UBVRI,
Halpha, [OIII] and [SII]} provided the identification of the most
relevant SF sites. In addition to our scientific analysis, we will
provide catalogs of HST photometry in 6 bands, matched corollary
ground-based data, and UV, Halpha and IR integrated measurements of
the associations, for comparison of integrated star-formation indices
to the resolved populations. We envisage an EPO component.

WFPC2 11070

WFPC2 CYCLE 15 Standard Darks - part II

This dark calibration program obtains dark frames every week in order
to provide data for the ongoing calibration of the CCD dark current
rate, and to monitor and characterize the evolution of hot pixels.
Over an extended period these data will also provide a monitor of
radiation damage to the CCDs.

WFPC2 11040

Geometric Distortion / Astrometry Closeout

These observations will serve as a final characterization of the
geometric distortion and astrometric calibration. The Omega-Cen inner
calibration field is used. Filters F300W, F555W, and F814W are
observed at 5 roll angles spanning 180 degrees; F218W is observed at a
single roll angle.

WFPC2 11024

WFPC2 CYCLE 15 INTERNAL MONITOR

This calibration proposal is the Cycle 15 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.

FGS 11019

Monitoring FGS1r's Interferometric Response as a Function of Spectral
Color

This proposal uses FGS1r in Transfer mode to observe standard single
stars of a variety of spectral types to obtain point source
interferograms for the Transfer mode calibration library. In specific
cases, the calibration star will also be observed in POS mode multiple
times with the F583W and F5ND elements to provide the data to verify
the stability of the cross filter calibration.

FGS 10928

Calibrating Cosmological Chronometers: White Dwarf Masses

We propose to use HST/FGS1R to determine White Dwarf {WD} masses. The
unmatched resolving power of HST/FGS1R will be utilized to follow up
four selected WD binary pairs. This high precision obtained with
HST/FGS1R simply cannot be equaled by any ground based technique. This
proposed effort complements that done by CoI Nelan in which a sample
of WDs is being observed with HST/FGS1R. This proposal will
dramatically increase the number of WDs for which dynamical mass
measurements are possible, enabling a better calibration of the WD
mass-radius relation, cooling curves, initial to final mass relations,
and ultimately giving important clues to the star formation history of
our Galaxy and the age of its disk as well as in other galaxies.

NIC3/WFPC2 10921

Tangential Velocities of Objects in the Orion Nebula and Locating the
Embedded Outflow Sources.

The Orion Nebula is arguably the Rosetta Stone for studying a very
young star cluster and how the radiation and outflowing plasma from
its stars interact with ambient material. It has been the subject of
numerous HST imaging studies, which means that there is good
opportunity for determining tangential velocities by obtaining second
epoch images during Cycle 15, which may be the last cycle for which
the WFPC2 is available. These velocities in the plane-of-the-sky will
allow us to determine the patterns of outflow from micro-jets smaller
than the Solar System to jet driven shocks more than a parsec from
their sources. Combined with radial velocities, we'll obtain spatial
velocities, which are critical to determining where the embedded
sources are located that produce the numerous HH objects coming from
the Orion-S and BN-KL regions. We'll also be able to determine the
physics that is operating in the LL Ori type of outflows {where a
bipolar jet is being distorted by a slow wind coming from the nebula}.
We will also be able to search for runaway stars caused by the
disintegration of young multiple-star systems. All of this is possible
because the long-time base of the WFPC2 and ACS observations allow a
new level of astrometric precision to be obtained and to be done
efficiently by making coordinated parallel observations with all
images.

WFPC2 10915

ACS Nearby Galaxy Survey

Existing HST observations of nearby galaxies comprise a sparse and
highly non-uniform archive, making comprehensive comparative studies
among galaxies essentially impossible. We propose to secure HST's
lasting impact on the study of nearby galaxies by undertaking a
systematic, complete, and carefully crafted imaging survey of ALL
galaxies in the Local Universe outside the Local Group. The resulting
images will allow unprecedented measurements of: {1} the star
formation history {SFH} of a 100 Mpc^3 volume of the Universe with a
time resolution of Delta[log{t}]=0.25; {2} correlations between
spatially resolved SFHs and environment; {3} the structure and
properties of thick disks and stellar halos; and {4} the color
distributions, sizes, and specific frequencies of globular and disk
clusters as a function of galaxy mass and environment. To reach these
goals, we will use a combination of wide-field tiling and pointed deep
imaging to obtain uniform data on all 72 galaxies within a
volume-limited sample extending to ~3.5 Mpc, with an extension to the
M81 group. For each galaxy, the wide-field imaging will cover out to
~1.5 times the optical radius and will reach photometric depths of at
least 2 magnitudes below the tip of the red giant branch throughout
the limits of the survey volume. One additional deep pointing per
galaxy will reach SNR~10 for red clump stars, sufficient to recover
the ancient SFH from the color-magnitude diagram. This proposal will
produce photometric information for ~100 million stars {comparable to
the number in the SDSS survey} and uniform multi- color images of half
a square degree of sky. The resulting archive will establish the
fundamental optical database for nearby galaxies, in preparation for
the shift of high- resolution imaging to the near-infrared.

WFPC2 10873

The Radio-quiet Jet Flow in Markarian 34

The properties of AGN jet flows are notoriously difficult to
ascertain. We are currently studying jets in Seyferts by combining
emission-line diagnostics with radio observations. We have devised a
method of analysis which -- with only modest and reasonable
assumptions -- leads to a physical description of the jet flow: its
mass, momentum and energy flux, along with its density, velocity and
Mach number. We have applied this method to a rich dataset on
Markarian 78 and discovered that its jet is very weak, slow, and dense
relative to the kind of jets found in radio loud AGN {Whittle \&
Wilson 2004, Whittle et al 2005, 2006}. Such a difference between
radio quiet and radio loud jet flows would be a major result -- if it
were found to be generally true. We have more modest observations of a
further six Seyferts with jets, but only one of these -- Mkn 34 --
approaches Mkn 78 as a clean enough case to allow our full analysis.
Our existing VLA and STIS data are excellent, but the HST archive
emission-line and continuum images are of poor quality and low
resolution. We are requesting just 3 orbits to obtain higher S/N
images at high resolution {ACS/HRC} in [OIII] 5007, [OII] 3727, green
and red continuum, bringing the total dataset up to a par with that of
Mkn 78. We will then be able to apply our full analysis to determine
the nature of the jet flow in this second radio quiet AGN.

NIC2 10854

Coronagraphic Imaging of Bright New Spitzer Debris Disks II.

Fifteen percent of bright main sequence stars possess dusty
circumstellar debris disks revealed by far-infrared photometry. These
disks are signposts of planetary systems: collisions among larger,
unseen parent bodies maintain the observed dust population against
losses to radiation pressure and P-R drag. Images of debris disks at
optical, infrared, and millimeter wavelengths have shown central
holes, rings, radial gaps, warps, and azimuthal asymmetries which
indicate the presence of planetary mass perturbers. Such images
provide unique insights into the structure and dynamics of
exoplanetary systems. Relatively few debris disks have been spatially
resolved. Only thirteen have ever been resolved at any wavelength, and
at wavelengths 10 microns {where subarcsec resolution is available},
only ten. Imaging of many other debris disk targets has been attempted
with various HST cameras/coronagraphs and adaptive optics, but without
success. The key property which renders a debris disk observable in
scattered light is its dust optical depth. The ten disks imaged so far
all have a dust excess luminosity ~ 0.01% that of the central star;
no disks with smaller optical depths have been detected. Most main
sequence stars known to meet this requirement have already been
observed, so future progress in debris disk imaging depends on
discovering additional stars with large infrared excess. The Spitzer
Space Telescope offers the best opportunity in 20 years to identify
new examples of high optical depth debris disk systems. We propose to
complete ACS coronagraphic imaging follow up of bright, new debris
disks discovered during the first two years of the Spitzer mission, by
observing three additional targets in Cycle 15. Our goal is to obtain
the first resolved images of these disks at ~3 AU resolution, define
the disk sizes and orientations, and uncover disk substructures
indicative of planetary perturbations. The results will open wider a
window into the structure of planetary systems.

WFPC2 10812

Space Motions for the Draco and Sextans Dwarf Spheroidal Galaxies

We will use the powerful astrometric capabilities of HST to measure
proper motions for the Draco and Sextans dwarf spheroidal galaxies
that will yield tangential velocities accurate to about 30 km/s. These
two galaxies are the last inside a galactocentric radius of 200~kpc
without measured proper motions. Knowing their orbits is critical for
our understanding of the low-luminosity satellites of the Milky Way.
In particular they are critical for understanding why Ursa Minor has
survived tidal disruption on its plunging orbit and how Carina formed
a large intermediate-age stellar population despite its small mass.

WFPC2 10787

Modes of Star Formation and Nuclear Activity in an Early Universe
Laboratory

Nearby compact galaxy groups are uniquely suited to exploring the
mechanisms of star formation amid repeated and ongoing gravitational
encounters, conditions similar to those of the high redshift universe.
These dense groups host a variety of modes of star formation, and they
enable fresh insights into the role of gas in galaxy evolution. With
Spitzer mid-IR observations in hand, we have begun to obtain high
quality, multi-wavelength data for a well- defined sample of 12 nearby
{4500km/s} compact groups covering the full range of evolutionary
stages. Here we propose to obtain sensitive BVI images with the
ACS/WFC, deep enough to reach the turnover of the globular cluster
luminosity function, and WFPC2 U-band and ACS H-alpha images of
Spitzer-identified regions hosting the most recent star formation. In
total, we expect to detect over 1000 young star clusters forming
inside and outside galaxies, more than 4000 old globular clusters in
40 giant galaxies {including 16 early-type galaxies}, over 20 tidal

features, approximately 15 AGNs, and intragroup gas in most of the 12
groups. Combining the proposed ACS images with Chandra observations,
UV GALEX observations, ground-based H-alpha imaging, and HI data, we
will conduct a detailed study of stellar nurseries, dust, gas
kinematics, and AGN.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

11113 - Loss of Lock while LOS

HST lost fine lock on FGS 1 and 2 at 356/00:27:52. P4TAKDAT (Take Data
Flag) went down at that time, causing four ACS 779 Status Buffer
Messages ("Fold Mechanism Move Was Blocked") to occur at 00:28:00,
00:37:54, 00:47:50 and 00:57:44. Upon acquisition of signal at
00:43:00 QF1STOPF was observed to be flagging.

11114 - GSacq (1,3,3) resulted in Fine Lock Back-up (1,0,1) using FGS
1

At 356/13:00:39, GSAcq (1,3,3) scheduled from 356/12:57:09 - 13:04:24
had failed to Fine Lock Back-up (1,0,1) using FGS 1, due to stop flags
QF3STOPF and QSTOP on FGS 3. Pre-acquisition OBAD #1 had an RSS value
of 472.38 arc seconds. Pre-acquisition OBAD #2 had an RSS value of
24.87 arc seconds. Post-acquisition OBAD Map had an RSS value of 11.01
arc seconds.

11116 - REacq (1,3,1) fine lock backup on FGS 1

REACQ(1,3,1) at 357/06:26:02 acquired in fine lock backup on FGS 1
only, with QF3STOPF and QSTOP flags set on FGS 3. No other flags were
seen. Initial GSACQ(1,3,1) at 03:15:01 and REACQ at 04:50:03 were
successful.

11117 - GSacq (1,2,2) failed, Search Radius Limit exceeded on FGS 1 @
358/0320z

GSACQ(1,2,2) at 03:20:53 failed with search radius limit exceeded on
FGS 1 at 03:26:40. One "A05" ESB message (FGS Coarse Track failed-
search Radius Limit exceeded) was received at 03:26:50.

OBADs prior to GSACQ had RSS errors of 1653.05 and 27.31 arcseconds,
OBAD map following GSACQ at 03:28:57 had RSS error of 572.46
arcseconds.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

************************* SCHEDULED***** SUCCESSFUL***** FAILURE
TIMES

FGS GSacq**************** 40***************** 39
FGS REacq**************** 30***************** 30
OBAD with Maneuver ***** 140************** * 139
LOSS of LOCK****************************************** @ 356/0027z

SIGNIFICANT EVENTS: (None)

 




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