HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science



DAILY REPORT # 4414



PERIOD COVERED: UT July 27,28,29, 2007 (DOY 208,209,210)



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 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.



WFPC2 11314



Calibration of MARCI UV using WFPC2



Ultraviolet imaging is a major unique component of the MARCI experiment

on MRO. Unfortunately the calibration of the UV, especially of the 260

nm filter, on MARCI is uncertain due to various unexpected problems

during laboratory calibration. Two orbits of WFPC2 observations are

requested to properly calibrate the UV using simultaneous MRO / HST

observations in a favorable geometry where HST is "looking over the

shoulder" of MRO.



WFPC2 11307



Completing the ACS Nearby Galaxy Survey with WFPC2



We are requesting 25 orbits of Director's Discretionary Time to complete

the primary science goals of our highly-ranked ACS Nearby Galaxy Survey

Treasury program {ANGST}. Our program lost ~2/3 of its orbits due to the

ACS failure. Roughly half of these were restored as a result of an

appeal to the Telescope Time Review Board which re-scoped the program.

The Board's response to our appeal was explicit in terms of which

targets were to be observed and how. We were directed to request

Director's discretionary time for the components of the appeal which

were not granted by the Review Board, but which were vital to the

success of the program. The observing strategy for ANGST is two-fold: to

obtain one deep field per galaxy which enables derivation of an accurate

ancient star formation history, and to obtain radial tilings sufficient

for recovering the full star formation history. The Review Board granted

WFPC2 observations for deep fields in 7 galaxies, but no time for radial

tilings. However, recovering the full star formation history of a galaxy

is not possible without additional radial coverage. We have searched the

archives for observations which may be used in place of the tilings

{conceding some of the Treasury goals, but providing significant

constraints on the full star formation history}, and have identified

suitable observations for all but two of the galaxies. Here we request

DD time for radial tilings for those last two galaxies.



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 flavor. 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 behavior in a substantially larger sample; ii} extend

the comparison between radio-loud and radio-quiet AGN to a larger range

of luminosities.



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!



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 z>6. 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.



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.



NIC2 11152



Probing the compact dust disk of a nearby Classical T Tauri Star



BP Psc is a high Galactic latitude {b = -57}, bright, IRAS source that

generally has been classified as a T Tauri star but little studied to

date. We have carried out a multiwavelength ground-based study of this

object and find that it is most likely a ~10 Myr classical T Tauri star

surrounded by a gas and dust disk, and less than 100 pc from Earth,

making it one of the oldest and closest such stars known. Near-IR AO

images and IR photometry show it is surrounded by an compact {0.2"},

almost-edge-on, optically thick disk of dust with a wide range of

temperatures. We propose a multiwavelength polarimetric study of the

compact disk to support quantitative modeling to recover disk and dust

parameters. We also propose coronagraphic imaging to search for larger-

scale dust structures invisible in ground-based images, and narrowband

imaging of an outflow jet and associated Herbig-Haro objects to study

their structure and determine a kinematic distance of the system. A

massive compact disk surrounding an isolated 10 Myr star is a unique

environment for planet formation, and its proximity to Earth allows HST

to study it in detail.



WFPC2 11118



Investigating Near-Equinox Atmospheric Change on Uranus



Uranus is approaching its 7 December 2007 equinox, when we will be able

to observe the entire northern hemisphere for the first time with modern

cameras. The large seasonal phase shift expected from its long radiative

time constant implies that it should now exhibit nearly maximal

hemispheric contrast, and should be in the process of reversing. Many

changes already observed, such as the development of the first

visible-wavelength dark spot, discovered in Cycle 15, and the fading of

the south polar cap may be indicative of the expected reversal. We

propose a detailed characterization of Uranus' current seasonal response

with a 7-orbit program consisting of 1 orbit of NICMOS imaging of cloud

bands and 6 orbits of WFPC2 imaging using both broadband and narrow-band

filters capable of tracking dark and bright discrete cloud features.

Filters between 0.467 and 1.87 microns will provide vertical sensing

depths scanning through the pressure range where the putative methane

and deeper H2S clouds might plausibly exist and provide strong

constraints on their contributions and parent gas mixing ratios. These

observations have unique combinations of spectral range and resolution

with needed temporal and spatial resolution not available from

groundbased observations. Only HST is capable of investigating the

Uranus dark spot.



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 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 11033



Full Moon Earth Flats Closeout



Flat field exposures will be obtained by observing the moonlit Earth

with the broadband WFPC2 filters F606W and F814W, which saturate in the

minimum exposure time on the sunlit Earth. These observations will be

used to improve the flats currently in the pipeline and are part of the

WFPC2 closeout operations. Because CTE effects are large for star flats

and small for full field illumination, Earth flats are the superior

technique.



WFPC2 10583



Resolving the LMC Microlensing Puzzle: Where Are the Lensing Objects ?



We are requesting 32 HST orbits to help ascertain the nature of the

population that gives rise to the observed set of microlensing events

towards the LMC. The SuperMACHO project is an ongoing ground-based

survey on the CTIO 4m that has demonstrated the ability to detect LMC

microlensing events in real-time via frame subtraction. The improvement

in angular resolution and photometric accuracy available from HST will

allow us to 1} confirm that the detected flux excursions arise from LMC

source stars rather than extended objects {such as for background

supernovae or AGN}, and 2} obtain reliable baseline flux measurements

for the objects in their unlensed state. The latter measurement is

important to resolve degeneracies between the event timescale and

baseline flux, which will yield a tighter constraint on the microlensing

optical depth.



FLIGHT OPERATIONS SUMMARY:



Significant Spacecraft Anomalies: (The following are preliminary reports

of potential non-nominal performance that will be investigated.)



HSTARS:



#10918 REacq(1,2,1) failed to RGA Control (Gyro Control).



REacq(1,2,1) scheduled at 209/13:56:20 - 14:04:25 failed to RGA Hold due

to (QF1STOPF) stop flag indication on FGS-1. Pre-acq OBADs showed (RSS)

attitude correction values of 888.95 and 17.77 arcseconds. Prior

GSAcq(1,2,1) of 209/12:40:12 was successful. Post-acq OBAD/MAP had (RSS) value of 10.04 arcseconds.



REacq(1,2,1) at 209/15:33:00 was successful. Upon acquisition of signal

at 209/17:23:59, HST was in Gyro Control with QF1STOPF and STOP flags

set. REacq(1,2,1) at 209/17:08:53 failed to RGA Hold.





#10919 GSAcq(1,3,3) results in fine lock backup (1,0,1).



Upon acquisition of signal at 209/19:08:11, the GSAcq(1,3,3) scheduled

at 209/18:49:46 - 18:57:51 had resulted in fine lock backup (1,0,1)

using FGS-1 due to (QF3STOPF) stop flag indication on the secondary

FGS-3. Pre-acq OBADs (RSS) attitude correction values not available due

to LOS. Post-acq OBAD/MAP showed (RSS) value of 13.60 arcseconds.



Subsequent REacq(1,3,3) scheduled at 209/20:24:07 resulted in fine lock

backup (1,0,1) using FGS-1 due to QF3STOPF stop flag indication on

FGS-3. Pre-acq OBADs were successful.





#10920 GSAcq (1,2,1) failed to RGA Hold (Gyro Control)



AT AOS 209/22:27:15 GSAcq (1,2,1) had failed to RGA Hold (Gyro Control)

with stop flags "QSTOP & QF1STOPF".



OBAD #1 & 2 data unavailable until engineering data dump is

accomplished. OBAD MAP: v1 6.30, V2 -0.41, V3 1.11, RSS 6.41.



At AOS 210/01:04:16 REAcq (1,2,1) scheduled from 209/23:32:20-23:39:50

had failed to RGA Hold (Gyro Control) with stop flags "QSTOP &

QF1STOPF". OBAD data unavailable due to LOS.



REAcq (1,2,1) scheduled from 210/01:08:14-01:15:44 failed to RGA Hold

(Gyro Control) with stop flags "QSTOP & QF1STOPF". FGS 1 reached a PMT

count high of 6393.00244.



OBAD #1: V1 -71.68, V2 -770.33, V3 -15.23, RSS 773.81 OBAD #2: V1 2.32,

V2 0.99, V3 -12.84, RSS 13.08 OBAD MAP: not scheduled



Note: The same guide star pair used in HSTAR 10918



COMPLETED OPS REQUEST: (None)



SCHEDULED SUCCESSFUL

FGS GSacq 22 21

FGS REacq 20 16

OBAD with Maneuver 84 84



COMPLETED OPS NOTES: (None)



SIGNIFICANT EVENTS: (None)