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      # 4336

 

PERIOD COVERED: UT April 07,08,09, 2007 (DOY 096,097,098)

 

OBSERVATIONS SCHEDULED

 

NIC1/NIC2/NIC3 8795

 

NICMOS Post-SAA calibration - CR Persistence Part 6

 

A new proceedure proposed to alleviate the CR-persistence problem of

NICMOS. Dark frames will be obtained immediately upon exiting the SAA

contour 23, and everytime 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 i

mages. Each observation will need its own CRMAP, as different SAA

passages leave different imprints on the NICMOS detectors.

 

NIC3 11082

 

NICMOS Imaging of GOODS: Probing the Evolution of the Earliest Massive

Galaxies, Galaxies Beyond

 

Deep near-infrared imaging provides the only avenue towards

understanding a host of astrophysical problems, including: finding

galaxies and AGN at z > 7, the evolution of the most massive galaxies,

the triggering of star formation in dusty galaxies, and revealing

properties of obscured AGN. As such, we propose to observe 60 selected

areas of the GOODS North and South fields with NICMOS Camera 3 in the

F160W band pointed at known massive M > 10^11 M_0 galaxies at z > 2

discovered through deep Spitzer imaging. The depth we will reach {26.5

AB at 5 sigma} in H_160 allows us to study the internal properties of

these galaxies, including their sizes and morphologies, and to

understand how scaling relations such as the Kormendy relationship

evolved. Although NIC3 is out of focus and undersampled, it is currently

our best opportunity to study these galaxies, while also sampling enough

area to perform a general NIR survey 1/3 the size of an ACS GOODS field.

These data will be a significant resource, invaluable for many other

science goals, including discovering high redshift galaxies at z > 7,

the evolution of galaxies onto the Hubble sequence, as well as examining

obscured AGN and dusty star formation at z > 1.5. The GOODS fields are

the natural location for HST to perform a deep NICMOS imaging program,

as extensive data from space and ground based observatories such as

Chandra, GALEX, Spitzer, NOAO, Keck, Subaru, VLT, JCMT, and the VLA are

currently available for these regions. Deep high-resolution

near-infrared observations are the one missing ingredient to this

survey, filling in an important gap to create the deepest, largest, and

most uniform data set for studying the faint and distant universe. The

importance of these images will increase with time as new facilities

come on line, most notably WFC3 and ALMA, and for the planning of future

JWST observations.

 

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 indvidual

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 11022

 

WFPC2 Cycle 15 Decontaminations and Associated Observations

 

This proposal is for the WFPC2 decons. Also included are instrument

monitors tied to decons: photometric stability check, focus monitor,

pre- and post-decon internals {bias, intflats, kspots, & darks}, UV

throughput check, VISFLAT sweep, and internal UV flat check.

 

FGS 10989

 

Astrometric Masses of Extrasolar Planets and Brown Dwarfs

 

We propose observations with HST/FGS to estimate the astrometric

elements {perturbation orbit semi-major axis and inclination} of

extra-solar planets orbiting six stars. These companions were originally

detected by radial velocity techniques. We have demonstrated that FGS

astrometry of even a short segment of reflex motion, when combined with

extensive radial velocity information, can yield useful inclination

information {McArthur et al. 2004}, allowing us to determine companion

masses. Extrasolar planet masses assist in two ongoing research

frontiers. First, they provide useful boundary conditions for models of

planetary formation and evolution of planetary systems. Second, knowing

that a star in fact has a plantary mass companion, increases the value

of that system to future extrasolar planet observation missions such as

SIM PlanetQuest, TPF, and GAIA.

 

WFPC2 10890

 

Morphologies of the Most Extreme High-Redshift Mid-IR-Luminous Galaxies

 

The formative phase 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,

restricting us to the study of 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 bright at mid-IR wavelengths

{F[24um]>0.8mJy}, but deep ground based imaging suggests extremely faint

{and in some cases extended} optical counterparts {R~24-27}. Deep K-band

images show barely resolved galaxies. Mid-infrared spectroscopy with

Spitzer/IRS reveals that they have redshifts z ~ 2-2.5, suggesting

bolometric luminosities ~10^{13-14}Lsun! We propose to obtain deep ACS

F814W and NIC2 F160W images of these sources and their environs in order

to determine kpc-scale morphologies and surface photometry for these

galaxies. The proposed observations will help us determine whether these

extreme 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 10886

 

The Sloan Lens ACS Survey: Towards 100 New Strong Lenses

 

As a continuation of the highly successful Sloan Lens ACS {SLACS} Survey

for new strong gravitational lenses, we propose one orbit of ACS-WFC

F814W imaging for each of 50 high-probability strong galaxy-galaxy lens

candidates. These observations will confirm new lens systems and permit

immediate and accurate photometry, shape measurement, and mass modeling

of the lens galaxies. The lenses delivered by the SLACS Survey all show

extended source structure, furnishing more constraints on the projected

lens potential than lensed-quasar image positions. In addition, SLACS

lenses have lens galaxies that are much brighter than their lensed

sources, facilitating detailed photometric and dynamical observation of

the former. When confirmed lenses from this proposal are combined with

lenses discovered by SLACS in Cycles 13 and 14, we expect the final

SLACS lens sample to number 80--100: an approximate doubling of the

number of known galaxy-scale strong gravitational lenses and an

order-of-magnitude increase in the number of optical Einstein rings. By

virtue of its homogeneous selection and sheer size, the SLACS sample

will allow an unprecedented exploration of the mass structure of the

early-type galaxy population as a function of all other observable

quantities. This new sample will be a valuable resource to the

astronomical community by enabling qualitatively new strong lensing

science, and as such we will waive all but a short {3-month} proprietary

period on the observations.

 

WFPC2 10880

 

The host galaxies of QSO2s: AGN feeding and evolution at high

luminosities

 

Now that the presence of supermassive black holes in the nuclei of

galaxies is a well established fact, other questions related to the AGN

phenomena still have to be answered. Problems of particular interest are

how the AGN gets fed, how the black hole evolves and how the evolution

of the black hole is related to the evolution of the galaxy bulge. Here

we propose to address some of these issues using ACS/WFC + F775W

snapshot images of 73 QSO2s with redshifts in the range 0.3<z<0.4. These

observations will be combined with similar archival data of QSO1s and

ground based data of Seyfert and normal galaxies. First, we will

intestigate whether interactions are the most important feeding

mechanism in high luminosity AGNs. This will be done in a quantitative

way, comparing the asymmetry indices of QSO2 hosts with those of lower

luminosity AGNs and normal galaxies. Second, we will do a detailed study

of the morphology of the host galaxies of both QSO types, to determine

if they are similar, or if there is an evolutionary trend from QSO2s to

QSO1s. The results from this project will represent an important step in

the understanding of AGN evolution, and may also introduce a substantial

modification to the Unified Model.

 

ACS/SBC 10872

 

Lyman Continuum Emission in Galaxies at z=1.2

 

Lyman continuum photons produced in massive starbursts may have played a

dominant role in the reionization of the Universe. Starbursts are

important contributors to the ionizing metagalactic background at lower

redshifts as well. However, their contribution to the background depends

upon the fraction of ionizing radiation that escapes from the intrinsic

opacity of galaxies below the Lyman limit. Current surveys suggest

escape fractions of a few percent, up to 10%, with very few detections

{as opposed to upper limits} having been reported. No detections have

been reported in the epochs between z=0.1 and z=2. We propose to measure

the fraction of escaping Lyman continuum radiation from 15 luminous

z~1.2 galaxies in the GOODS fields. Using the tremendous sensitivity of

the ACS Solar- blind Channel, we will reach AB=30 mag., allowing us to

detect an escape fraction of 1%. We will correlate the amount of

escaping radiation with the photometric and morphological properties of

the galaxies. A non-detection in all sources would imply that QSOs

provide the overwhelming majority of ionizing radiation at z=1.3, and it

would strongly indicate that the properties of galaxies at higher

redshift have to be significantly different for galaxies to dominate

reionization. The deep FUV images will also be useful for extending the

FUV study of other galaxies in the GOODS fields.

 

NIC1 10859

 

Precise Measurements of Sgr A* Flare Activity

 

Correlated X-ray and near-IR flare emission from Sgr A*, the closest

supermassive black hole, contains information about the hydrodynamics,

energetics, and accretion behavior of matter within the innermost ten

Schwarzschild radii of the hole. We propose HST/NICMOS observations of

near-IR flares, in conjunction with already approved obsrevations using

XMM-Newton {214 ksec} and CSO {3 nights}, which can make the precise,

new measurements necessary to understand the radiation mechanism and low

luminosity of Sgr A*. HST/NICMOS is required due to its very low and

stable background, and its stable, tightly focused PSF, which allow

accurate measurement of fainter flares than can be observed using

groundbased adaptive optics systems. We will measure the spectral index

distribution, the time-averaged flux and duration of flares, and the

statistics of flare activity, and will confirm previously reported

quasi-periodic variability. These measurements will have far-reaching

implications for testing the inverse Compton scattering {ICS} and

synchrotron models of low-luminosity flares, for understanding the

process of accretion onto and outflow from supermassive black holes, and

for constraining the acceleration mechanism of flares and the inferred

black hole spin. This knowledge, in turn, will help us understand more

generally low-luminosity AGN and X-ray binaries in a very low/quiescent

accretion state.

 

WFPC2 10786

 

Rotational state and composition of Pluto's outer satellites

 

We propose an intricate set of observations aimed at discovering the

rotational state of the newly discovered satellites of Pluto, S/2005 P1

and S/2005 P2. These observations will indicate if the satellites are in

synchronous rotation or not. If they are not, then the observations will

determine the rotational period or provide tight constraints on the

amplitude. The other primary goal is to extend the wavelength coverage

of the colors of the surface and allow us to constrain the surface

compositions of both objects. From these data we will also be able to

significantly improve the orbits of P1 and P2, improve the measurement

of the bulk density of Charon, and search for albedo changes on the

surface of Pluto.

 

NIC2 10599

 

Multi-color imaging of two 1 Gyr old debris disks within 20 pc of the

Sun: Astrophysical mirrors of our Kuiper Belt

 

We report the first scattered light detections of two debris disk around

an F star and a K star using optical coronagraphy and the Hubble Space

Telescope. With ages ~1 Gyr, these are the oldest debris disks thus far

seen in the optical. We propose deep, multi-roll angle coronagraphic

imaging with HST ACS and NICMOS to confirm and characterize the disks in

terms of structure and composition. The disks appear to have belt-like

morphology that is consistent with the existence of planetary companions

or other perturbing bodies. Since these disks are close to our Kuiper

Belt in an evolutionary context, detailed understanding of their mass,

structure and composition will provide a fresh perspective for inferring

the history and properties of our own trans-Neptunian region.

 

FLIGHT OPERATIONS SUMMARY:

 

Significant Spacecraft Anomalies: (The following are preliminary reports

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

 

HSTARS:

10769 - GSAcq (1,2,2) failed to RGA control

           At AOS 096/10:05:16 GSAcq (1,2,2) scheduled from 096/08:38:21-08:45:41

           had failed to RGA control (Gyro Hold) due to QSTOP flag on FGS 1.

 

           OBAD MAP: V1 107.01, V2 -402.65, V3 -335.62, RSS 535.02

 

           (This failure occurred during an LOS in the previous reporting period @

           096/08:38:21z, and so is not counted as a failure for this reporting

           period.)

 

 

10770 - GSAcq(1,3,3) failed to RGA Hold (Gyro Control)

           Upon acquisition of signal at 098/19:24:30, the GSAcq(1,3,3) scheduled

           at 098/19:15:04 - 19:23:09 had failed to RGA Hold due to (QF1STOPF) stop

           flag indication on FGS1. Pre-acquisition OBADs (RSS) attitude correction

           values not available due to LOS. Post-acq OBAD/MAP had (RSS) value of

           18.13 arcseconds. 

 

 

COMPLETED OPS REQUEST: (None)

 

COMPLETED OPS NOTES: (None)

 

                        SCHEDULED      SUCCESSFUL   

FGS GSacq                27                  26     

FGS REacq               10                   10                 

OBAD with Maneuver 76                   76                

 

SIGNIFICANT EVENTS: (None)