Notice: For the foreseeable future, the daily reports may contain

apparent discrepancies between some proposal descriptions and the listed

instrument usage. This is due to the conversion of previously approved

ACS WFC or HRC observations into WFPC2, or NICMOS observations

subsequent to the loss of ACS CCD science capability in late January.

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4397

PERIOD COVERED: UT June 03, 04, 2007 (DOY 184, 185)

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.

WFPC2 11292

The Ring Plane Crossings of Uranus in 2007

The rings of Uranus turn edge-on to Earth in May and August 2007. In

between, we will have a rare opportunity to see the unlit face of the

rings. With the nine optically thick rings essentially invisible, we will

observe features and phenomena that are normally lost in their glare. We

will use this opportunity to search thoroughly for the embedded

"shepherd" moons long believed to confine the edges of the rings,

setting a mass limit roughly 10 times smaller than that of the smallest

shepherd currently known, Cordelia. We will measure the vertical

thicknesses of the rings and study the faint dust belts only known to

exist from a single Voyager image. We will also study the colors of the

newly-discovered faint, outer rings; recent evidence suggests that one

ring is red and the other blue, implying that each ring is dominated by

a different set of physical processes. We will employ near- edge-on

photometry from 2006 and 2007 to derive the particle filling factor

within the rings, to observe how ring epsilon responds to the "traffic

jam" as particles pass through its narrowest point, and to test the

latest models for preserving eccentricities and apse alignment within

the rings. Moreover, this data set will allow us to continue monitoring

the motions of the inner moons, which have been found to show possibly

chaotic orbital variations; by nearly doubling the time span of the

existing Hubble astrometry, the details of the variations will become

much clearer.

WFPC2 11289

SL2S: The Strong Lensing Legacy Survey

Recent systematic surveys of strong galaxy-galaxy lenses {CLASS, SLACS,

GOODS, etc.} are producing spectacular results for galaxy masses roughly

below a transition mass M~10^13 Mo. The observed lens properties and

their evolution up to z~0.2, consistent with numerical simulations, can

be described by isothermal elliptical potentials. In contrast, modeling

of giant arcs in X-ray luminous clusters {halo masses M >~10^13 Mo}

favors NFW mass profiles, suggesting that dark matter halos are not

significantly affected by baryon cooling. Until recently, lensing

surveys were neither deep nor extended enough to probe the intermediate

mass density regime, which is fundamental for understanding the assembly

of structures. The CFHT Legacy Survey now covers 125 square degrees, and

thus offers a large reservoir of strong lenses probing a large range of

mass densities up to z~1. We have extracted a list of 150 strong lenses

using the most recent CFHTLS data release via automated procedures.

Following our first SNAPSHOT proposal in cycle 15, we propose to

continue the Hubble follow-up targeting a larger list of 130 lensing

candidates. These are intermediate mass range candidates {between

galaxies and clusters} that are selected in the redshift range of 0.2-1

with no a priori X-ray selection. The HST resolution is necessary for

confirming the lensing candidates, accurate modeling of the lenses, and

probing the total mass concentration in galaxy groups up to z~1 with the

largest unbiased sample available to date.

ACS/SBC 11225

The Wavelength Dependence of Accretion Disk Structure

We can now routinely measure the size of quasar accretion disks using

gravitational microlensing of lensed quasars. The next step to testing

accretion disk models is to measure the size of accretion disks as a

function of wavelength, particularly at the UV and X-ray wavelengths

that should probe the inner, strong gravity regime. Here we focus on two

four-image quasar lenses that already have optical {R band} and X-ray

size measurements using microlensing. We will combine the HST

observations with ground-based monitoring to measure the disk size as a

function of wavelength from the near-IR to the UV. We require HST to

measure the image flux ratios in the ultraviolet continuum near the

Lyman limit of the quasars. The selected targets have estimated black

hole masses that differ by an order of magnitude, and we should find

wavelength scaling for the two systems that are very different because

the Blue/UV wavelengths should correspond to parts of the disk near the

inner edge for the high mass system but not in the low mass system. The

results will be modeled using a combination of simple thin disk models

and complete relativistic disk models. While requiring only 18 orbits,

success for one system requires observations in both Cycles 16 and 17.

FGS 11210

The Architecture of Exoplanetary Systems

Are all planetary systems coplanar? Concordance cosmogony makes that

prediction. It is, however, a prediction of extrasolar planetary system

architecture as yet untested by direct observation for main sequence

stars other than the Sun. To provide such a test, we propose to carry

out FGS astrometric studies on four stars hosting seven companions. Our

understanding of the planet formation process will grow as we match not

only system architecture, but formed planet mass and true distance from

the primary with host star characteristics for a wide variety of host

stars and exoplanet masses. We propose that a series of FGS astrometric

observations with demonstrated 1 millisecond of arc per- observation

precision can establish the degree of coplanarity and component true

masses for four extrasolar systems: HD 202206 {brown dwarf+planet}; HD

128311 {planet+planet}, HD 160691 = mu Arae {planet+planet}, and HD

222404AB = gamma Cephei {planet+star}. In each case the companion is

identified as such by assuming that the minimum mass is the actual mass.

For the last target, a known stellar binary system, the companion orbit

is stable only if coplanar with the AB binary orbit.

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.

NIC2 11157

NICMOS Imaging Survey of Dusty Debris Around Nearby Stars Across the

Stellar Mass Spectrum

Association of planetary systems with dusty debris disks is now quite

secure, and advances in our understanding of planet formation and

evolution can be achieved by the identification and characterization of

an ensemble of debris disks orbiting a range of central stars with

different masses and ages. Imaging debris disks in starlight scattered

by dust grains remains technically challenging so that only about a

dozen systems have thus far been imaged. A further advance in this field

needs an increased number of imaged debris disks. However, the technical

challenge of such observations, even with the superb combination of HST

and NICMOS, requires the best targets. Recent HST imaging investigations

of debris disks were sample-limited not limited by the technology used.

We performed a search for debris disks from a IRAS/Hipparcos cross

correlation which involved an exhaustive background contamination check

to weed out false excess stars. Out of ~140 identified debris disks, we

selected 22 best targets in terms of dust optical depth and disk angular

size. Our target sample represents the best currently available target

set in terms of both disk brightness and resolvability. For example, our

targets have higher dust optical depth, in general, than newly

identified Spitzer disks. Also, our targets cover a wider range of

central star ages and masses than previous debris disk surveys. This

will help us to investigate planetary system formation and evolution

across the stellar mass spectrum. The technical feasibility of this

program in two-gyro mode guiding has been proven with on- orbit

calibration and science observations during HST cycles 13, 14, and 15.

NIC2 11101

The Relevance of Mergers for Fueling AGNs: Answers from QSO Host

Galaxies

The majority of QSOs are known to reside in centers of galaxies that

look like ellipticals. Numerical simulations have shown that remnants of

galaxy mergers often closely resemble elliptical galaxies. However, it

is still strongly debated whether the majority of QSO host galaxies are

indeed the result of relatively recent mergers or whether they are

completely analogous to inactive ellipticals to which nothing

interesting has happened recently. To address this question, we recently

obtained deep HST ACS images for five QSO host galaxies that were

classified morphologically as ellipticals {GO-10421}. This pilot study

revealed striking signs of tidal interactions such as ripples, tidal

tails, and warped disks that were not detected in previous studies. Our

observations show that at least some "elliptical" QSO host galaxies are

the products of relatively recent merger events rather than old galaxies

formed at high redshift. However, the question remains whether the host

galaxies of classical QSOs are truly distinct from inactive ellipticals

and whether there is a connection between the merger events we detect

and the current nuclear activity. We must therefore place our results

into a larger statistical context. We are currently conducting an HST

archival study of inactive elliptical galaxies {AR-10941} to form a

control sample. We now propose to obtain deep HST/WFPC2 images of 13

QSOs whose host galaxies are classified as normal ellipticals. Comparing

the results for both samples will help us determine whether classical

QSOs reside in normal elliptical galaxies or not. Our recent pilot study

of five QSOs indicates that we can expect exciting results and deep

insights into the host galaxy morphology also for this larger sample of

QSOs. A statistically meaningful sample will help us determine the true

fraction of QSO hosts that suffered strong tidal interactions and thus,

whether a merger is indeed a requirement to trigger nuclear activity in

the most luminous AGNs. In addition to our primary science observations

with WFPC2, we will obtain NICMOS3 parallel observations with the

overall goal to select and characterize galaxy populations at high

redshifts. The imaging will be among the deepest NICMOS images: These

NICMOS images are expected to go to a limit a little over 1 magnitude

brighter than HUDF-NICMOS data, but over 13 widely separated fields,

with a total area about 1.5 times larger than HUDF-NICMOS. This

separation means that the survey will tend to average out effects of

cosmic variance. The NICMOS3 images will have sufficient resolution for

an initial characterization of galaxy morphologies, which is currently

one of the most active and promising areas in approaching the problem of

the formation of the first massive galaxies. The depth and area coverage

of our proposed NICMOS observations will also allow a careful study of

the mass function of galaxies at these redshifts. This provides a large

and unbiased sample, selected in terms of stellar mass and unaffected by

cosmic variance, to study the on-going star formation activity as a

function of mass {i.e. integrated star formation} at this very important

epoch.

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.

NIC1 11063

NICMOS Focus Monitoring

This program is a version of the standard focus sweep used since cycle

7. It has been modified to go deeper and uses more narrow filters for

improved focus determination. For Cycle14 a new source has been added in

order to accommodate 2-gyro mode: the open cluster NGC1850. The old

target, the open cluster NGC3603, will be used whenever available and

the new target used to fill the periods when NGC3603 is not visible.

Steps: a} Use refined target field positions as determined from cycle 7

calibrations b} Use MULTIACCUM sequences of sufficient dynamic range to

account for defocus c} Do a 17- point focus sweep, +/- 8mm about the PAM

mechanical zeropoint for each cameras 1 and 2, in 1.0mm steps. d} Use

PAM X/Y tilt and OTA offset slew compensations refined from previous

focus monitoring/optical alignment activities

NIC3 11062

NICMOS non-linearity tests

This program incorporates a number of tests to analyse the count rate

dependent non- linearity seen in NICMOS spectro-photometric

observations. We will observe a field with stars of a range in

luminosity in NGC3603 with NICMOS in NIC1: F090M, F110W, F140W, F160W

NIC2: F110W, F160W, F187W, F205W, and F222M NIC3: F110W, F150W, F160W,

F175W, and F222M. We will repeat the observations with flatfield lamp

on, creating artificially high count-rates, allowing tests of NICMOS

linearity as function of count rate. We first take exposures with the

lamp off, then exposures with the lamp on, and repeat at the end with

lamp off. Finally, we continue with taking darks during occultation. We

will furthermore observe spectro-photometric standard P041C using the

G096, G141, and G206 grisms in NIC3, and repeat the lamp off/on/off test

to artificially create a high background.

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 11028

WFPC2 Cycle 15 UV Earth Flats

Monitor flat field stability. This proposal obtains sequences of earth

streak flats to improve the quality of pipeline flat fields for the

WFPC2 UV filter set. These Earth flats will complement the UV earth flat

data obtained during cycles 8-14.

WFPC2 10841

A Proper Motion Search for Intermediate Mass Black Holes in Globular

Clusters {2nd Epoch Observations}

Establishing the presence or absence of intermediate-mass black holes

{IMBH} in globular clusters is crucial for understanding the evolution

of dense stellar systems. Observationally, this search has been hampered

by the low number of stars with known velocities in the central few

arcseconds. This limits our knowledge of the velocity dispersion in the

region where the gravitational influence of any IMBH would be felt. In

Cycle 13, we successfully obtained ACS/HRC images of the centers of five

carefully chosen Galactic globular clusters {GO-10401} for a new proper

motion study. Although the science case was approved and the first epoch

images obtained, the requested future cycle observations were not

granted {due to a general policy decision based on the strong

uncertainties at the time concerning the immediate future of HST}. We

have now assessed the quality of the first epoch observations. The HRC

resolution reveals many isolated stars in to the very center of each

cluster that remained blended or unresolved in previous WFPC2 data.

Given a two year baseline, we are confident that we can achieve the

proper motion precision required to place strict limits on the presence

of an IMBH. Therefore, we request the second-epoch, follow-up

observations to GO-10401 in order to measure the proper motions of stars

in our target clusters. These velocity measurements will allow us to:

{i} place constraints on the mass of a central black hole in each

cluster; {ii} derive the internal velocity dispersion as a function of

cluster radius; {iii} verify or reject previous reports of cluster

rotation; and {iv} directly measure velocity anisotropy as a function of

radius. If no second epoch data are obtained then the observing time

already invested in the first epoch will have been wasted.

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: #10878 GSacq (1,2,1) failed to RGA control. GSacq(1,2,1)

scheduled at 184/15:52:25 failed during LOS due to receiving a stop flag

on FGS 2. OBAD1 at 15:47:26 showed errors of V1=-19.30, V2=1449.10,

V3=-565.83, RSS=1555.77. OBAD2 showed errors of V1=13.76, V2=5.33,

V3=2.58, RSS=14.98

#10879 GSacq(1,3,3) failed to RGA control. GSacq(1,3,3) scheduled at

185/11:08:28 failed during LOS due to receiving a stop flag on FGS 1.

The map at 11:15:27 showed errors of V1=-0.13, V2=3.33, V3=5.72,

RSS=6.62.

COMPLETED OPS REQUEST: (None)

                              SCHEDULED SUCCESSFUL

FGS GSacq                      16              14

FGS REacq                      12              12

OBAD with Maneuver        56              56

COMPLETED OPS NOTES: (None)

SIGNIFICANT EVENTS: (None)