HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT      #4949

PERIOD COVERED: 5am October 9 - 5am October 13, 2009 (DOY 282/09:00z-286/09:00z)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA Calibration - CR Persistence Part 6

This is 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 'Use After' 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.

NIC1/NIC2/NIC3 11947

Extended Dark Monitoring

This program takes a series of darks to obtain darks (including

amplifier glow, dark current, and shading profiles) for all three

cameras in the read-out sequences used in Cycle 17. A set of 12 orbits

will be observed every two months for a total of 72 orbits for a 12

month Cycle 17. This is a continuation of Cycle 16 program 11330 scaled

down by ~80%.

The first orbit (Visit A0) should be scheduled in the NICMOS SMOV after

the DC Transfer Test (11406) and at least 36h before the Filter Wheel

Test (11407). Data download using fast track.

The following 28 orbits (visit A1-N2) should be scheduled AFTER the SMOV

Proposal 11407 (Filter Wheel Test). This is done in order to monitor the

dark current following an adjustment of the NCS set-point. These visits

should be executed until the final temperature is reached during SMOV.

WFC3/IR/S/C 11929

IR Dark Current Monitor

Analyses of ground test data showed that dark current signals are more

reliably removed from science data using darks taken with the same

exposure sequences as the science data, than with a single dark current

image scaled by desired exposure time. Therefore, dark current images

must be collected using all sample sequences that will be used in

science observations. These observations will be used to monitor changes

in the dark current of the WFC3-IR channel on a day-to-day basis, and to

build calibration dark current ramps for each of the sample sequences to

be used by GOs in Cycle 17. For each sample sequence/array size

combination, a median ramp will be created and delivered to the

calibration database system (CDBS).

WFC3/UVIS 11908

Cycle 17: UVIS Bowtie Monitor

Ground testing revealed an intermittent hysteresis type effect in the

UVIS detector (both CCDs) at the level of ~1%, lasting hours to days.

Initially found via an unexpected bowtie-shaped feature in flatfield

ratios, subsequent lab tests on similar e2v devices have since shown

that it is also present as simply an overall offset across the entire

CCD, i.e., a QE offset without any discernable pattern. These lab tests

have further revealed that overexposing the detector to count levels

several times full well fills the traps and effectively neutralizes the

bowtie. Each visit in this proposal acquires a set of three 3x3 binned

internal flatfields: the first unsaturated image will be used to detect

any bowtie, the second, highly exposed image will neutralize the bowtie

if it is present, and the final image will allow for verification that

the bowtie is gone.

WFC3/UVIS 11907

UVIS Cycle 17 Contamination Monitor

The UV throughput of WFC3 during Cycle 17 is monitored via weekly

standard star observations in a subset of key filters covering 200-600nm

and F606W, F814W as controls on the red end. The data will provide a

measure of throughput levels as a function of time and wavelength,

allowing for detection of the presence of possible contaminants.

WFC3/UVIS 11905

WFC3 UVIS CCD Daily Monitor

The behavior of the WFC3 UVIS CCD will be monitored daily with a set of

full-frame, four-amp bias and dark frames. A smaller set of 2Kx4K

subarray biases are acquired at less frequent intervals throughout the

cycle to support subarray science observations. The internals from this

proposal, along with those from the anneal procedure (Proposal 11909),

will be used to generate the necessary superbias and superdark reference

files for the calibration pipeline (CDBS).

COS/FUV 11895

FUV Detector Dark Monitor

The purpose of this proposal is to monitor the FUV detector dark rate by

taking long science exposures without illuminating the detector. The

detector dark rate and spatial distribution of counts will be compared

to pre-launch and SMOV data in order to verify the nominal operation of

the detector. Variations of count rate as a function of orbital position

will be analyzed to find dependence of dark rate on proximity to the

SAA. Dependence of dark rate as function of time will also be tracked.

ACS/WFC3 11879

CCD Daily Monitor (Part 1)

This program comprises basic tests for measuring the read noise and dark

current of the ACS WFC and for tracking the growth of hot pixels. The

recorded frames are used to create bias and dark reference images for

science data reduction and calibration. This program will be executed

four days per week (Mon, Wed, Fri, Sun) for the duration of Cycle 17. To

facilitate scheduling, this program is split into three proposals. This

proposal covers 352 orbits (22 weeks) from 31 August 2009 to 31 January

2010.

STIS/CCD 11846

CCD Bias Monitor-Part 1

The purpose of this proposal is to monitor the bias in the 1x1, 1x2,

2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up

high-S/N superbiases and track the evolution of hot columns.

STIS/CCD 11844

CCD Dark Monitor Part 1

The purpose of this proposal is to monitor the darks for the STIS CCD.

WFC3/IR 11838

Completing a Flux-limited Survey for X-ray Emission from Radio Jets

We will measure the changing flow speeds, magnetic fields, and energy

fluxes in well-resolved quasar jets found in our short-exposure Chandra

survey by combining new, deep Chandra data with radio and optical

imaging. We will image each jet with sufficient sensitivity to estimate

beaming factors and magnetic fields in several distinct regions, and so

map the variations in these parameters down the jets. HST observations

will help diagnose the role of synchrotron emission in the overall SED,

and may reveal condensations on scales less than 0.1 arcsec.

STIS/CCD 11806

Coordinated Observations of LCROSS Impacts

We propose to observe the LCROSS (Lunar Crater Observation and Sensing

Satellite) impacts. This program will use STIS and WFC3 to observe the

Moon in conjunction with NASA's LCROSS mission (assuming Servicing

Mission 4 occurs before the LCROSS impacts). The goal is to determine

whether or not water ice and/or vapor is present in the subsurface of

the Moon. We will address this issue by 1) observing the sunlit ejecta

plume created by the LCROSS impacts and 2) examine the Lunar exosphere

for the presence of OH and other volatile species.

WFC3/UVIS 11729

Photometric Metallicity Calibration with WFC3 Specialty Filters

The community has chosen to include several filters in the WFC3 filter

complement that have been designed to allow fairly precise estimates of

stellar metallicities, and many science programs are enabled by this

capability. Since these filters do not exactly match those used for this

purpose on the ground, however, the mapping of stellar colors to stellar

metallicities needs to be calibrated. We propose to achieve this

calibration through observations of five stellar clusters with well

known metallicities. We will calibrate several different filter

calibrations which will allow future users to determine what filter

combination best meets their science needs.

WFC3/UVIS 11714

Snapshot Survey for Planetary Nebulae in Local Group Globular Clusters

Planetary nebulae (PNe) in globular clusters (GCs) raise a number of

interesting issues related to stellar and galactic evolution. The number

of PNe known in Milky Way GCs, four, is surprisingly low if one assumes

that all stars pass through a PN stage. However, it is likely that the

remnants of stars now evolving in galactic GCs leave the AGB so slowly

that any ejected nebula dissipates long before the star becomes hot

enough to ionize it. Thus there should not be ANY PNe in Milky Way

GCs--but there are four! It has been suggested that these PNe are the

result of mergers of binary stars within GCs, i.e., that they are

descendants of blue stragglers. The frequency of occurrence of PNe in

external galaxies poses more questions, because it shows a range of

almost an order of magnitude.

I propose a SNAPshot survey aimed at discovering PNe in the GC systems

of Local Group galaxies outside the Milky Way. These clusters, some of

which may be much younger than their counterparts in our galaxy, might

contain many more PNe than those of our own galaxy. I will use the

standard technique of emission-line and continuum imaging, which easily

discloses PNe. This proposal continues a WFPC2 program started in Cycle

16, but with the more powerful WFC3. As a by-product, the survey will

also produce color-magnitude diagrams for numerous clusters for the

first time, reaching down to the horizontal branch.

FGS 11704

The Ages of Globular Clusters and the Population II Distance Scale

Globular clusters are the oldest objects in the universe whose age can

be accurately determined. The dominant error in globular cluster age

determinations is the uncertain Population II distance scale. We propose

to use FGS 1R to obtain parallaxes with an accuracy of 0.2

milliarcsecond for 9 main sequence stars with [Fe/H] < -1.5. This will

determine the absolute magnitude of these stars with accuracies of 0.04

to 0.06mag. This data will be used to determine the distance to 24

metal-poor globular clusters using main sequence fitting. These

distances (with errors of 0.05 mag) will be used to determine the ages

of globular clusters using the luminosity of the subgiant branch as an

age indicator. This will yield absolute ages with an accuracy of 5%,

about a factor of two improvement over current estimates. Coupled with

existing parallaxes for more metal-rich stars, we will be able to

accurately determine the age for globular clusters over a wide range of

metallicities in order to study the early formation history of the Milky

Way and provide an independent estimate of the age of the universe.

The Hipparcos database contains only 1 star with [Fe/H] < -1.4 and an

absolute magnitude error less than 0.18 mag which is suitable for use in

main sequence fitting. Previous attempts at main sequence fitting to

metal-poor globular clusters have had to rely on theoretical

calibrations of the color of the main sequence. Our HST parallax program

will remove this source of possible systematic error and yield distances

to metal-poor globular clusters which are significantly more accurate

than possible with the current parallax data. The HST parallax data will

have errors which are 10 times smaller than the current parallax data.

Using the HST parallaxes, we will obtain main sequence fitting distances

to 11 globular clusters which contain over 500 RR Lyrae stars. This will

allow us to calibrate the absolute magnitude of RR Lyrae stars, a

commonly used Population II distance indicator.

WFC3/UV/ACS/WFC 11688

Exploring the Bottom End of the White Dwarf Cooling Sequence in the Open

Cluster NGC6819

The recent discovery by our group of an unexpectedly bright end of the

white-dwarf (WD) luminosity function (LF) of the metal-rich, old open

cluster NGC 6791 casts serious doubts on our understanding of the

physical process which rules the formation and the cooling of WDs. It is

clear at this point that the theory badly needs more observations. Here

we propose WFC3/UVIS and ACS/WFC HST observations reaching the bottom

end of the WD LF, for the first time in a solar-metallicity,

2.5-Gyr-old, populous open cluster: NGC 6819.

COS/FUV 11687

SNAPing Coronal Iron

This is a Snapshot Survey to explore two forbidden lines of highly

ionized iron in late-type coronal sources. Fe XII 1349 (T~ 2 MK) and Fe

XXI 1354 (T~ 10 MK) -- well known to Solar Physics -- have been detected

in about a dozen cool stars, mainly with HST/STIS. The UV coronal

forbidden lines are important because they can be observed with velocity

resolution of better than 15 km/s, whereas even the state-of-the-art

X-ray spectrometers on Chandra can manage only 300 km/s in the kilovolt

band where lines of highly ionized iron more commonly are found. The

kinematic properties of hot coronal plasmas, which are of great interest

to theorists and modelers, thus only are accessible in the UV at

present. The bad news is that the UV coronal forbidden lines are faint,

and were captured only in very deep observations with STIS. The good

news is that 3rd-generation Cosmic Origins Spectrograph, slated for

installation in HST by SM4, in a mere 25 minute exposure with its G130M

mode can duplicate the sensitivity of a landmark 25-orbit STIS E140M

observation of AD Leo, easily the deepest such exposure of a late-type

star so far. Our goal is to build up understanding of the properties of

Fe XII and Fe XXI in additional objects beyond the current limited

sample: how the lineshapes depend on activity, whether large scale

velocity shifts can be detected, and whether the dynamical content of

the lines can be inverted to map the spatial morphology of the stellar

corona (as in "Doppler Imaging''). In other words, we want to bring to

bear in the coronal venue all the powerful tricks of spectroscopic

remote sensing, well in advance of the time that this will be possible

exploiting the corona's native X-ray radiation. The 1290-1430 band

captured by side A of G130M also contains a wide range of key plasma

diagnostics that form at temperatures from below 10, 000 K (neutral

lines of CNO), to above 200, 000 K (semi-permitted O V 1371), including

the important bright multiplets of C II at 1335 and Si IV at 1400;

yielding a diagnostic gold mine for the subcoronal atmosphere. Because

of the broad value of the SNAP spectra, beyond the coronal iron project,

we waive the normal proprietary rights.

WFC3/UV/IR 11664

The WFC3 Galactic Bulge Treasury Program: Populations, Formation

History, and Planets

Exploiting the full power of the Wide Field Camera 3 (WFC3), we propose

deep panchromatic imaging of four fields in the Galactic bulge. These

data will enable a sensitive dissection of its stellar populations,

using a new set of reddening-free photometric indices we have

constructed from broad-band filters across UV, optical, and near-IR

wavelengths. These indices will provide accurate temperatures and

metallicities for hundreds of thousands of individual bulge stars.

Proper motions of these stars derived from multi-epoch observations will

allow separation of pure bulge samples from foreground disk

contamination. Our catalogs of proper motions and panchromatic

photometry will support a wide range of bulge studies.

Using these photometric and astrometric tools, we will reconstruct the

detailed star-formation history as a function of position within the

bulge, and thus differentiate between rapid- and extended-formation

scenarios. We will also measure the dependence of the stellar mass

function on metallicity, revealing how the characteristic mass of star

formation varies with chemistry. Our sample of bulge stars with accurate

metallicities will include 12 candidate hosts of extrasolar planets.

Planet frequency is correlated with metallicity in the solar

neighborhood; our measurements will extend this knowledge to a remote

environment with a very distinct chemistry.

Our proposal also includes observations of six well-studied globular and

open star clusters; these observations will serve to calibrate our

photometric indices, provide empirical population templates, and

transform the theoretical isochrone libraries into the WFC3 filter

system. Besides enabling our own program, these products will provide

powerful new tools for a host of other stellar-population investigations

with HST/WFC3. We will deliver all of the products from this Treasury

Program to the community in a timely fashion.

WFC3/UVIS 11657

The Population of Compact Planetary Nebulae in the Galactic Disk

We propose to secure narrow- and broad-band images of compact planetary

nebulae (PNe) in the Galactic Disk to study the missing link of the

early phases of post-AGB evolution. Ejected AGB envelopes become PNe

when the gas is ionized. PNe expand, and, when large enough, can be

studied in detail from the ground. In the interim, only the HST

capabilities can resolve their size, morphology, and central stars. Our

proposed observations will be the basis for a systematic study of the

onset of morphology. Dust properties of the proposed targets will be

available through approved Spitzer/IRS spectra, and so will the

abundances of the alpha- elements. We will be able thus to explore the

interconnection of morphology, dust grains, stellar evolution, and

populations. The target selection is suitable to explore the nebular and

stellar properties across the galactic disk, and to set constraints on

the galactic evolutionary models through the analysis of metallicity and

population gradients.

WFC3/UVIS 11594

A WFC3 Grism Survey for Lyman Limit Absorption at z=2

We propose to conduct a spectroscopic survey of Lyman limit absorbers at

redshifts 1.8 < z < 2.5, using WFC3 and the G280 grism. This proposal

intends to complete an approved Cycle 15 SNAP program (10878), which was

cut short due to the ACS failure. We have selected 64 quasars at 2.3 < z

< 2.6 from the Sloan Digital Sky Survey Spectroscopic Quasar Sample, for

which no BAL signature is found at the QSO redshift and no strong metal

absorption lines are present at z > 2.3 along the lines of sight. The

survey has three main observational goals. First, we will determine the

redshift frequency dn/dz of the LLS over the column density range 16.0 <

log(NHI) < 20.3 cm^-2. Second, we will measure the column density

frequency distribution f(N) for the partial Lyman limit systems (PLLS)

over the column density range 16.0 < log(NHI) < 17.5 cm^-2. Third, we

will identify those sightlines which could provide a measurement of the

primordial D/H ratio. By carrying out this survey, we can also help

place meaningful constraints on two key quantities of cosmological

relevance. First, we will estimate the amount of metals in the LLS using

the f(N), and ground based observations of metal line transitions.

Second, by determining f(N) of the PLLS, we can constrain the amplitude

of the ionizing UV background at z~2 to a greater precision. This survey

is ideal for a snapshot observing program, because the on-object

integration times are all well below 30 minutes, and follow-up

observations from the ground require minimal telescope time due to the

QSO sample being bright.

COS/FUV 11592

Testing the Origin(s) of the Highly Ionized High-Velocity Clouds: A

Survey of Galactic Halo Stars at z>3 kpc

Cosmological simulation predicts that highly ionized gas plays an

important role in the formation and evolution of galaxies and their

interplay with the intergalactic medium. The NASA HST and FUSE missions

have revealed high-velocity CIV and OVI absorption along extragalactic

sightlines through the Galactic halo. These highly ionized high-velocity

clouds (HVCs) could cover 85% of the sky and have a detection rate

higher than the HI HVCs. Two competing, equally exciting, theories may

explain the origin of these highly ionized HVCs: 1) the "Galactic"

theory, where the HVCs are the result of feedback processes and trace

the disk-halo mass exchange, perhaps including the accretion of matter

condensing from an extended corona; 2) the "Local Group" theory, where

they are part of the local warm-hot intergalactic medium, representing

some of the missing baryonic matter of the Universe. Only direct

distance determinations can discriminate between these models. Our group

has found that some of these highly ionized HVCs have a Galactic origin,

based on STIS observations of one star at z<5.3 kpc. We propose an HST

FUV spectral survey to search for and characterize the high velocity NV,

CIV, and SiIV interstellar absorption toward 24 stars at much larger

distances than any previous searches (4<d<21 kpc, 3<|z|<13 kpc). COS

will provide atomic to highly ionized species (e.g., OI, CII, CIV, SiIV)

that can be observed at sufficient resolution (R~22, 000) to not only

detect these highly ionized HVCs but also to model their properties and

understand their physics and origins. This survey is only possible

because of the high sensitivity of COS in the FUV spectral range.

ACS/WFC3 11586

Exceptional Galactic Halo Globular Clusters and the Second Parameter

We propose to obtain deep ACS-WFC images of six globular clusters (five

of which have no previous HST photometry) that reside in the Galactic

halo, where the second parameter effect is most pronounced. These

globular clusters are among the least studied in the Galaxy and yet,

from the perspective of the second parameter phenomenon, the most

intriguing.

With the best available CMDs only reaching the vicinity of the main

sequence turn off at present, the unique sensitivity and resolution of

ACS-WFC will yield ages of unprecedented precision for these clusters.

These data will provide us with new insight into the stellar populations

present in the outer Galactic halo and the nature of the second

parameter. The second parameter plays a critical role in our

understanding of the formation and evolution of the Galaxy and the

proposed observations will shed new light on this problem and these

exceptional clusters.

WFC3/UVI 11580

Watching Young Planetary Nebulae Grow: The Movie

The development of magneto-hydro gas dynamical models is the key to the

understanding of both the physics (processes) and astronomy (initial

conditions) of astrophysical nebulae of all sorts. The models are

reaching their highest degree of accuracy when applied to and compared

against pre Planetary Nebulae (pPNe) thanks to the simplicity, relative

lack of extinction, and the detail of the imaging and kinematic data

that have bcome available for these objects. The primary barrier to

progress is inadequate kinematic data of pPNe against which the

predictions models can be tested. Unlike PNe, pPNe do not emit emission

lines for detailed Doppler measurements. Therefore it is essential to

find another way to monitor the morphological evolution.

Only HST can uncover the dynamics of the growth patterns by subtracting

multi-epoch images spanning a decade or more. We have selected four pPNe

with highly collimated outflows in different evolutionary stages for

which high-quality first epoch images were obtained from 1996 to 2002.

All of them display regularly shaped thin rims, sharp edges, and

symmetric pairs of knots or bowshocks that are ideal for our purposes.

We will closely mimic many of the earlier exposures using ACS and to

monitor changes in structures. The morphology and its evolution will be

compared to 3-D MHD models with adaptive grids in order to build a far

clearer picture of the nuclear geometry which shaped the outflows and

constrained their propagation to the present. We shall also obtain R, J,

and H images for use with a 3-D dust radiative transfer code LELUYA to

model the dust distribution deep into the nuclear zones.

NIC2/WFC3/IR 11548

Infrared Imaging of Protostars in the Orion A Cloud: The Role of

Environment in Star Formation

We propose NICMOS and WFC3/IR observations of a sample of 252 protostars

identified in the Orion A cloud with the Spitzer Space Telescope. These

observations will image the scattered light escaping the protostellar

envelopes, providing information on the shapes of outflow cavities, the

inclinations of the protostars, and the overall morphologies of the

envelopes. In addition, we ask for Spitzer time to obtain 55-95 micron

spectra of 75 of the protostars. Combining these new data with existing

3.6 to 70 micron photometry and forthcoming 5-40 micron spectra measured

with the Spitzer Space Telescope, we will determine the physical

properties of the protostars such as envelope density, luminosity,

infall rate, and outflow cavity opening angle. By examining how these

properties vary with stellar density (i.e. clusters vs. groups vs.

isolation) and the properties of the surrounding molecular cloud; we can

directly measure how the surrounding environment influences protostellar

evolution, and consequently, the formation of stars and planetary

systems. Ultimately, this data will guide the development of a theory of

protostellar evolution.

COS/NUV/FUV/WFC3/UVI 11534 S/IR COS-GTO: Atmosphere of a Transiting

Planet

COS observations of a transiting planet at different orbital locations

will be useful in identifying the chemical content, size, temperature,

and flows in the atmosphere of a transiting planet.

NIC 11408

NICMOS Focus and PAM Grid Tilt Tests

The purpose of this proposal is determine the PAM settings corresponding

to best focus for NIC1 and NIC2. A test will aslo be done on NIC3 in

order to establish that the nominal PAM position of -9.5mm relative to

mechanical zero results in an acceptable focus.

The program consists of: Visit 01: Focus sweep using NIC1 Visit 02:

Focus sweep using NIC2 Visit 03: Focus sweep using NIC3 Visit 04: Uplink

of revised PAM settings (if needed) Visit 05: PAM X/Y grid tilt for NIC1

Visit 06: PAM X/Y grid tilt for NIC2 Visit 07: PAM X/Y grid tilt for

NIC3 Visit 08: Uplink of revised PAM X/Y parameters (if needed)

The focus sweeps are based on the normal focus monitoring proposal

11320. The tilt grid measurements are based on proposal 8977 (NIC1) and

9645 (NIC2 and NIC3).

WFC3/ACS/IR 11359

Panchromatic WFC3 Survey of Galaxies at Intermediate z: Early Release

Science Program for Wide Field Camera 3

The unique panchromatic capabilities of WFC3 will be used to survey the

structure and evolution of galaxies at the peak of the galaxy assembly

epoch. Deep ultraviolet and near-IR imaging and slitless spectroscopy of

existing deep multi-color ACS fields will be used to gauge

star-formation and the growth of stellar mass as a function of

morphology, structure and surrounding density in the critical epoch 1 <

z < 4. Images in the F225W, F275W, and F336W filters will identify

galaxies at z < 1.5 from their UV continuum breaks, and provide

star-formation indicators tied directly to both local and z > 3

populations. Deep near-IR (F125W and F160W) images will probe the

stellar mass function well below 10^9 Msun for mass-complete samples.

Lastly, the WFC3 slitless UV and near-IR grisms will be used to measure

redshifts and star-formation rates from H-alpha and rest-frame UV

continuum slope. This WFC3 ERS program will survey one 4 x 2 mosaic for

a total area of 50 square arcminutes to 5-sigma depths of m_AB = 27 in

most filters from the mid-UV through the near-IR.

This multicolor high spatial resolution data set will allow the user to

gauge the growth of galaxies through star-formation and merging. High

precision photometric and low-resolution spectroscopic redshifts will

allow accurate determinations of the faint-end of the luminosity and

mass functions, and will shed light on merging and tidal disruption of

stellar and gaseous disks. The WFC3 images will also allow detailed

studies of the internal structure of galaxies, and the distribution of

young and old stellar populations. This program will demonstrate the

unique power of WFC3 by applying its many diverse modes and full

panchromatic capability to a forefront problem in astrophysics.

ACS/WFC3 11343

Identifying the Host Galaxies for Optically Dark Gamma-Ray Bursts

We propose to use the high spatial resolution capabilities of Chandra to

obtain precise positions for a sample of Gamma-ray bursts (GRBs) with no

optical afterglows, where the optical light is suppressed relative to

the X-ray flux. These bursts are likely to be highly obscured and may

have different environments from the optically bright GRBs. Our Chandra

observations will (unlike Swift-XRT positions) allow for the unique

identification of a host galaxy. To locate these host galaxies we will

follow up our Chandra positions with deep optical and IR observations

with HST. The ultimate aim is to understand any differences between the

host galaxies of optically dark and bright GRBs, and how these affect

the use of GRBs as tracers of star formation and galaxy evolution at

high redshift.

WFC3/IR 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

WFC3 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!

WFC3/ACS/IR 11142

Revealing the Physical Nature of Infrared Luminous Galaxies at 0.3<z<2.7

Using HST and Spitzer

We aim to determine physical properties of IR luminous galaxies at

0.3<z<2.7 by requesting coordinated HST/NIC2 and MIPS 70um observations

of a unique, 24um flux-limited sample with complete Spitzer mid-IR

spectroscopy. The 150 sources investigated in this program have S(24um)

> 0.8mJy and their mid-IR spectra have already provided the majority

targets with spectroscopic redshifts (0.3<z<2.7). The proposed

150~orbits of NIC2 and 66~hours of MIPS 70um will provide the physical

measurements of the light distribution at the rest-frame ~8000A and

better estimates of the bolometric luminosity. Combining these

parameters together with the rich suite of spectral diagnostics from the

mid-IR spectra, we will (1) measure how common mergers are among LIRGs

and ULIRGs at 0.3<z<2.7, and establish if major mergers are the drivers

of z>1 ULIRGs, as in the local Universe, (2) study the co-evolution of

star formation and blackhole accretion by investigating the relations

between the fraction of starburst/AGN measured from mid-IR spectra vs.

HST morphologies, L(bol) and z, and (3) obtain the current best

estimates of the far-IR emission, thus L(bol) for this sample, and

establish if the relative contribution of mid-to-far IR dust emission is

correlated with morphology (resolved vs. unresolved).

NIC2 10897

Coronagraphic imaging of the submillimeter debris disk of a 200Myr old

M-dwarf

A recent sub-millimeter survey has unambiguously discovered a new debris

disk around the M0.5 dwarf GJ842.2 which is 200 Myr old. Reanalysis of

the IRAS data has shown that there is also a 25 micron excess toward

this star indicating warm dust close to the star. It is also only the

second debris disk found among M-dwarfs that constitute 70 % of the

stars in the Galaxy. Collisional and Poynting-Roberston timescale

arguments indicate that the cold grains detected in the sub-mm are

``primordial'', i.e. original grains from the protoplanetary phase. The

disk around GJ842.2 is thus unique in terms of the presence of dust at

such a late stage of evolution and presents two conundrums: why did it

retain so much primordial dust at large distances, and why does it

continue to produce dust close to the star? We propose to conduct high

contrast NICMOS coronagraphic imaging of GJ842.2 to determine the

spatial distribution of the small reflecting grains and test the various

scenarios which might explain the IRAS and sub-mm data e.g.resonant

trapping of dust by planets or ``sandblasting'' by interstellar medium

grains working more aggressively on a low-luminosity star than on an

A-type star like Beta Pic. Also, we would search for an evolutionary

sequence between GJ842.2 and the only other M-dwarf with a disk resolved

by HST, the 10 Myr old AU Mic system.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

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

HSTARS:

12040 - GSAcq(1,2,1) scheduled at 283/03:37:59 - 03:45:30 failed to RGA

           Hold (gyro control) due to search radius limit exceeded on FGS-2

           Observations affected: STIS 89 Proposal ID# 10897.

12041 - GSAcq(1,2,1) scheduled at 286/02:05:19 - 02:12:50 and

           REAcq(1,2,1) scheduled at 286/03:28:54 both resulted in fine lock backup

           (1,0,1) using FGS-1.

           Observations possibly affected: STIS 10, Proposal ID# 11846 and

           WFC3 36-37, Proposal ID# 11202.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                       SCHEDULED      SUCCESSFUL

FGS GSAcq               40                  39  

FGS REAcq               21                  21                 

OBAD with Maneuver 34                  34                

SIGNIFICANT EVENTS: (None)