HUBBLE SPACE TELESCOPE - Continuing to Collect World Class Science

DAILY REPORT #5140

PERIOD COVERED: 5am July 16 - 5am July 19, 2010 (DOY 197/09:00z-200/09:00z)

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

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

HSTARS:

#12330  REAcq(1,2,1) @197/19:28z and 21:04z failed to RGA, Scan Step Limit on FGS1

               Observations affected: COS #54-59 and ACS #120-126 Proposal #11658

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                           SCHEDULED      SUCCESSFUL

GSAcq                         25              25 

FGS REAcq                  24              22               

OBAD with Maneuver   20              20               

SIGNIFICANT EVENTS: (None)

OBSERVATIONS SCHEDULED:

WFC3/UV/ACS/WFC/IR 12057

A Panchromatic Hubble Andromeda Treasury - I

We propose to image the north east quadrant of M31 to deep limits in the

UV, optical, and near-IR. HST imaging should resolve the galaxy into

more than 100 million stars, all with common distances and foreground

extinctions. UV through NIR stellar photometry (F275W, F336W with

WFC3/UVIS, F475W and F814W with ACS/WFC, and F110W and F160W with

WFC3/NIR) will provide effective temperatures for a wide range of

spectral types, while simultaneously mapping M31's extinction. Our

central science drivers are to: understand high-mass variations in the

stellar IMF as a function of SFR intensity and metallicity; capture the

spatially-resolved star formation history of M31; study a vast sample of

stellar clusters with a range of ages and metallicities. These are

central to understanding stellar evolution and clustered star formation;

constraining ISM energetics; and understanding the counterparts and

environments of transient objects (novae, SNe, variable stars, x-ray

sources, etc.). As its legacy, this survey adds M31 to the Milky Way and

Magellanic Clouds as a fundamental calibrator of stellar evolution and

star-formation processes for understanding the stellar populations of

distant galaxies. Effective exposure times are 977s in F275W, 1368s in

F336W, 4040s in F475W, 4042s in F814W, 699s in F110W, and 1796s in

F160W, including short exposures to avoid saturation of bright sources.

These depths will produce photon-limited images in the UV. Images will

be crowding-limited in the optical and NIR, but will reach below the red

clump at all radii. The images will reach the Nyquist sampling limit in

F160W, F475W, and F814W.

S/C 12046

COS FUV DCE Memory Dump

Whenever the FUV detector high voltage is on, count rate and current

draw information is collected, monitored, and saved to DCE memory. Every

10 msec the detector samples the currents from the HV power supplies

(HVIA, HVIB) and the AUX power supply (AUXI). The last 1000 samples are

saved in memory, along with a histogram of the number of occurrences of

each current value.

In the case of a HV transient (known as a "crackle" on FUSE), where one

of these currents exceeds a preset threshold for a persistence time, the

HV will shut down, and the DCE memory will be dumped and examined as

part of the recovery procedure. However, if the current exceeds the

threshold for less than the persistence time (a "mini-crackle" in FUSE

parlance), there is no way to know without dumping DCE memory. By

dumping and examining the histograms regularly, we will be able to

monitor any changes in the rate of "mini-crackles" and thus learn

something about the state of the detector.

ACS/WFC 11996

CCD Daily Monitor (Part 3)

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 308 orbits (19.25 weeks) from 21 June 2010 to 1 November

2010.

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).

STIS/MA1/MA2 11857

STIS Cycle 17 MAMA Dark Monitor

This proposal monitors the behavior of the dark current in each of the

MAMA detectors.

The basic monitor takes two 1380s ACCUM darks each week with each

detector. However, starting Oct 5, pairs are only included for weeks

that the LRP has external MAMA observations planned. The weekly pairs of

exposures for each detector are linked so that they are taken at

opposite ends of the same SAA free interval. This pairing of exposures

will make it easier to separate long and short term temporal variability

from temperature dependent changes.

For both detectors, additional blocks of exposures are taken once every

six months. These are groups of five 1314s FUV-MAMA Time-Tag darks or

five 3x315s NUV ACCUM darks distributed over a single SAA-free interval.

This will give more information on the brightness of the FUV MAMA dark

current as a function of the amount of time that the HV has been on, and

for the NUV MAMA will give a better measure of the short term

temperature dependence.

STIS/CC 11847

CCD Bias Monitor-Part 2

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/CC 11845

CCD Dark Monitor Part 2

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.

COS/NUV/FUV 11728

The Impact of Starbursts on the Gaseous Halos of Galaxies

Perhaps the most important (yet uncertain) aspects of galaxy evolution

are the processes by which galaxies accrete gas and by which the

resulting star formation and black hole growth affects this accreting

gas. It is believed that both the form of the accretion and the nature

of the feedback change as a function of the galaxy mass. At low mass the

gas comes in cold and the feedback is provided by massive stars. At high

mass, the gas comes in hot, and the feedback is from an AGN. The

changeover occurs near the mass where the galaxy population transitions

from star-forming galaxies to red and dead ones. The population of red

and dead galaxies is building with cosmic time, and it is believed that

feedback plays an important role in this process: shutting down star

formation by heating and/or expelling the reservoir of cold halo gas. To

investigate these ideas, we propose to use COS far-UV spectra of

background QSOs to measure the properties of the halo gas in a sample of

galaxies near the transition mass that have undergone starbursts within

the past 100 Myr to 1 Gyr. The galactic wind associated with the

starburst is predicted to have affected the properties of the gaseous

halo. To test this, we will compare the properties of the halos of the

post-starburst galaxies to those of a control sample of galaxies matched

in mass and QSO impact parameter. Do the halos of the post-starburst

galaxies show a higher incidence rate of Ly-Alpha and metal

absorption-lines? Are the kinematics of the halo gas more disturbed in

the post-starbursts? Has the wind affected the ionization state and/or

the metallicity of the halo? These data will provide fresh new insights

into the role of feedback from massive stars on the evolution of

galaxies, and may also offer clues about the properties of the QSO metal

absorption-line systems at high-redshift .

WFC3/IR 11712

Calibration of Surface Brightness Fluctuations for WFC3/IR

We aim to characterize galaxy surface brightness fluctuations (SBF), and

calibrate the SBF distance method, in the F110W and F160W filters of the

Wide Field Camera 3 IR channel. Because of the very high throughput of

F110W and the good match of F160W to the standard H band, we anticipate

that both of these filters will be popular choices for galaxy

observations with WFC3/IR. The SBF signal is typically an order of

magnitude brighter in the near-IR than in the optical, and the

characteristics (sensitivity, FOV, cosmetics) of the WFC3/IR channel

will be enormously more efficient for SBF measurements than previously

available near-IR cameras. As a result, our proposed SBF calibration

will allow accurate distance derivation whenever an early-type or

bulge-dominated galaxy is observed out to a distance of 150 Mpc or more

(i.e., out to the Hubble flow) in the calibrated passbands. For

individual galaxy observations, an accurate distance is useful for

establishing absolute luminosities, black hole masses, linear sizes,

etc. Eventually, once a large number of galaxies have been observed

across the sky with WFC3/IR, this SBF calibration will enable accurate

mapping of the total mass density distribution in the local universe

using the data available in the HST archive. The proposed observations

will have additional important scientific value; in particular, we

highlight their usefulness for understanding the nature of multimodal

globular cluster color distributions in giant elliptical galaxies.

WFC3/UVIS 11697

Proper Motion Survey of Classical and SDSS Local Group Dwarf Galaxies

Using the superior resolution of HST, we propose to continue our proper

motion survey of Galactic dwarf galaxies. The target galaxies include

one classical dwarf, Leo II, and six that were recently identified in

the Sloan Digital Sky Survey data: Bootes I, Canes Venatici I, Canes

Venatici II, Coma Berenices, Leo IV, and Ursa Major II. We will observe

a total of 16 fields, each centered on a spectroscopically-confirmed

QSO. Using QSOs as standards of rest in measuring absolute proper

motions has proven to be the most accurate and most efficient method.

HST is our only option to quickly determine the space motions of the

SDSS dwarfs because suitable ground-based imaging is only a few years

old and such data need several decades to produce a proper motion. The

two most distant galaxies in our sample will require time baselines of

four years to achieve our goal of a 30-50 km/s uncertainty in the

tangential velocity; given this and the finite lifetime of HST, it is

imperative that first-epoch observations be taken in this cycle. The

SDSS dwarfs have dramatically lower surface brightnesses and

luminosities than the classical dwarfs. Proper motions are crucial for

determining orbits of the galaxies and knowing the orbits will allow us

to test theories for the formation and evolution of these galaxies and,

more generally, for the formation of the Local Group.

WFC3/IR 11696

Infrared Survey of Star Formation Across Cosmic Time

We propose to use the unique power of WFC3 slitless spectroscopy to

measure the evolution of cosmic star formation from the end of the

reionization epoch at z>6 to the close of the galaxy- building era at

z~0.3.Pure parallel observations with the grisms have proven to be

efficient for identifying line emission from galaxies across a broad

range of redshifts. The G102 grism on WFC3 was designed to extend this

capability to search for Ly-alpha emission from the first galaxies.

Using up to 250 orbits of pure parallel WFC3 spectroscopy, we will

observe about 40 deep (4-5 orbit) fields with the combination of G102

and G141, and about 20 shallow (2-3 orbit) fields with G141 alone.

Our primary science goals at the highest redshifts are: (1) Detect Lya

in ~100 galaxies with z>5.6 and measure the evolution of the Lya

luminosity function, independent of of cosmic variance; 2) Determine the

connection between emission line selected and continuum-break selected

galaxies at these high redshifts, and 3) Search for the proposed

signature of neutral hydrogen absorption at re-ionization. At

intermediate redshifts we will (4) Detect more than 1000 galaxies in

Halpha at 0.5<z<1.8 to measure the evolution of the extinction-corrected

star formation density across the peak epoch of star formation. This is

over an order-of-magnitude improvement in the current statistics, from

the NICMOS Parallel grism survey. (5) Trace ``cosmic downsizing" from

0.5<z<2.2; and (6) Estimate the evolution in reddening and metallicty in

star- forming galaxies and measure the evolution of the Seyfert

population. For hundreds of spectra we will be able to measure one or

even two line pair ratios -- in particular, the Balmer decrement and

[OII]/[OIII] are sensitive to gas reddening and metallicity. As a bonus,

the G102 grism offers the possibility of detecting Lya emission at

z=7-8.8.

To identify single-line Lya emitters, we will exploit the wide

0.8--1.9um wavelength coverage of the combined G102+G141 spectra. All

[OII] and [OIII] interlopers detected in G102 will be reliably separated

from true LAEs by the detection of at least one strong line in the G141

spectrum, without the need for any ancillary data. We waive all

proprietary rights to our data and will make high-level data products

available through the ST/ECF.

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/IR 11666

Chilly Pairs: A Search for the Latest-type Brown Dwarf Binaries and the

Prototype Y Dwarf

We propose to use HST/WFC3 to image a sample of 27 of the nearest (< 20

pc) and lowest luminosity T-type brown dwarfs in order to identify and

characterize new very low mass binary systems. Only 3 late-type T dwarf

binaries have been found to date, despite that fact that these systems

are critical benchmarks for evolutionary and atmospheric models at the

lowest masses. They are also the most likely systems to harbor Y dwarf

companions, an as yet unpopulated putative class of very cold (T < 600

K) brown dwarfs. Our proposed program will more than double the number

of T5-T9 dwarfs imaged at high resolution, with an anticipated yield of

~5 new binaries with initial characterization of component spectral

types. We will be able to probe separations sufficient to identify

systems suitable for astrometric orbit and dynamical mass measurements.

We also expect one of our discoveries to contain the first Y-type brown

dwarf. Our proposed program complements and augments ongoing

ground-based adaptive optics surveys and provides pathway science for

JWST.

WFC3/UVIS 11661

The Black Hole Mass - Bulge Luminosity Relationship for the Nearest

Reverberation-Mapped AGNs

We propose to obtain WFC3 host galaxy images of the eight nearest AGNs

with masses from reverberation mapping, and one star as a PSF model.

These images will allow us to determine with unprecedented accuracy the

bulge luminosities of the host galaxies, a goal which is not achievable

from the ground due to the blurring of the very bright PSF component

under typical, and even very good, seeing conditions. High-resolution

ACS images of the host galaxies of more luminous AGNs reveal that the

black hole mass-bulge luminosity and black hole mass-bulge mass

relationships for AGNs are not well constrained and arise from what

appear to be fundamentally flawed data sets. With the addition of the

images proposed here to our current sample of ACS images, we will be

able to extend our determinations of the black hole mass- bulge

luminosity and black hole mass-bulge mass relationships for AGNs by an

order of magnitude and test our preliminary results for these

fundamentally important relationships against those previously

determined for quiescent galaxies.

COS/NUV/ACS/WFC/FUV 11658

Probing the Outer Regions of M31 with QSO Absorption Lines

We propose HST-COS spectroscopy of 10 quasars behind M31. Absorption

lines due to MgII, FeII, CIV, and a variety of other lines will be

searched for and measured. Six quasars lie between 1 and 4.2 Holmberg

radii near the major axis on the southwest side, where confusion with

Milky Way gas is minimized. Two lie even farther out on the southwest

side of the major axis. One lies within 1 Holmberg radius. Two of the 10

pass through M31's high velocity clouds seen in a detailed 21 cm

emission map. Exposure time estimates were based on SDSS magnitudes and

available GALEX magnitudes. Thus, using the most well-studied external

spiral galaxy in the sky, our observations will permit us to check,

better than ever before, the standard picture that quasar metal-line

absorption systems such as MgII and CIV arise in an extended gaseous

halo/disk of a galaxy well beyond its observable optical radius. The

observations will yield insights into the nature of the gas and its

connection to the very extended stellar components of M31 that have

recently been studied. Notably the observations have the potential of

extending M31's rotation curve to very large galactocentric distances,

thereby placing new constraints on M31's dark matter halo.

Finally, we also request that the coordinated parallel orbits be

allocated to this program so that we may image the resolved stellar

content of M31's halo and outer disk.

WFC3/IR 11631

Binary Brown Dwarfs and the L/T Transition

Brown dwarfs traverse spectral types M, L and T as their atmospheric

structure evolves and they cool into oblivion. This SNAPSHOT program

will obtain WFC3-IR images of 45 nearby late-L and early-T dwarfs to

investigate the nature of the L/T transition. Recent analyses have

suggested that a substantial proportion of late-L and early-T dwarfs are

binaries, comprised of an L dwarf primary and T dwarf secondary. WFC3-IR

observations will let us quantify this suggestion by expanding coverage

to a much larger sample, and permitting comparison of the L/T binary

fraction against ‘normal’ ultracool dwarfs. Only eight L/T binaries are

currently known, including several that are poorly resolved: we

anticipate at least doubling the number of resolved systems. The

photometric characteristics of additional resolved systems will be

crucial to constraining theoretical models of these late-type ultracool

dwarfs. Finally, our data will also be eminently suited to searching for

extremely low luminosity companions, potentially even reaching the Y

dwarf regime.

WFC3/ACS/UVIS 11613

GHOSTS: Stellar Outskirts of Massive Spiral Galaxies

We propose to continue our highly successful GHOSTS HST survey of the

resolved stellar populations of nearby, massive disk galaxies using

SNAPs. These observations provide star counts and color-magnitude

diagrams 2-3 magnitudes below the tip of the Red Giant Branch of the

outer disk and halo of each galaxy. We will measure the metallicity

distribution functions and stellar density profiles from star counts

down to very low average surface brightnesses, equivalent to ~32 V-mag

per square arcsec.

This proposal will substantially improve our unique sampling of galaxy

outskirts. Our targets cover a range in galaxy mass, luminosity,

inclination, and morphology. As a function of these galaxy properties,

this survey provides: - the most extensive, systematic measurement of

radial light profiles and axial ratios of the diffuse stellar halos and

outer disks of spiral galaxies; - a comprehensive analysis of halo

metallicity distributions as function of galaxy type and position within

the galaxy; - an unprecedented study of the stellar metallicity and age

distribution in the outer disk regions where the disk truncations occur;

- the first comparative study of globular clusters and their field

stellar populations.

We will use these fossil records of the galaxy assembly process to test

halo formation models within the hierarchical galaxy formation scheme.

COS/NUV/FUV 11598

How Galaxies Acquire their Gas: A Map of Multiphase Accretion and

Feedback in Gaseous Galaxy Halos

We propose to address two of the biggest open questions in galaxy

formation - how galaxies acquire their gas and how they return it to the

IGM - with a concentrated COS survey of diffuse multiphase gas in the

halos of SDSS galaxies at z = 0.15 - 0.35. Our chief science goal is to

establish a basic set of observational facts about the physical state,

metallicity, and kinematics of halo gas, including the sky covering

fraction of hot and cold material, the metallicity of infall and

outflow, and correlations with galaxy stellar mass, type, and color -

all as a function of impact parameter from 10 - 150 kpc. Theory suggests

that the bimodality of galaxy colors, the shape of the luminosity

function, and the mass-metallicity relation are all influenced at a

fundamental level by accretion and feedback, yet these gas processes are

poorly understood and cannot be predicted robustly from first

principles. We lack even a basic observational assessment of the

multiphase gaseous content of galaxy halos on 100 kpc scales, and we do

not know how these processes vary with galaxy properties. This ignorance

is presently one of the key impediments to understanding galaxy

formation in general. We propose to use the high-resolution gratings

G130M and G160M on the Cosmic Origins Spectrograph to obtain sensitive

column density measurements of a comprehensive suite of multiphase ions

in the spectra of 43 z < 1 QSOs lying behind 43 galaxies selected from

the Sloan Digital Sky Survey. In aggregate, these sightlines will

constitute a statistically sound map of the physical state and

metallicity of gaseous halos, and subsets of the data with cuts on

galaxy mass, color, and SFR will seek out predicted variations of gas

properties with galaxy properties. Our interpretation of these data will

be aided by state-of-the-art hydrodynamic simulations of accretion and

feedback, in turn providing information to refine and test such models.

We will also use Keck, MMT, and Magellan (as needed) to obtain optical

spectra of the QSOs to measure cold gas with Mg II, and optical spectra

of the galaxies to measure SFRs and to look for outflows. In addition to

our other science goals, these observations will help place the Milky

Way's population of multiphase, accreting High Velocity Clouds (HVCs)

into a global context by identifying analogous structures around other

galaxies. Our program is designed to make optimal use of the unique

capabilities of COS to address our science goals and also generate a

rich dataset of other absorption-line systems.

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.

WFC3/UVIS 11577

Opening New Windows on the Antennae with WFC3

We propose to use WFC3 to provide key observations of young star

clusters in "The Antennae" (NGC4038/39). Of prime importance is the

WFC3's ability to push the limiting UV magnitude FIVE mag deeper than

our previous WFPC2 observations. This corresponds to pushing the

limiting cluster mass from ~10**5 to ~10**3 solar masses for cluster

ages ~10**8 yrs. In addition, the much wider field of view of the WFC3

IR channel will allow us to map out both colliding disks rather than

just the Overlap Region between them. This will be especially important

for finding the youngest clusters that are still embedded in their

placental cocoons. The extensive set of narrow-band filters will provide

an effective means for determining the properties of shocks, which are

believed to be a primary triggering mechanism for star formation. We

will also use ACS in parallel with WFC3 to observe portions of both the

northern and southern tails at no additional orbital cost. Finally, one

additional primary WFC3 orbit will be used to supplement exisiting HST

observations of the star-forming "dwarf" galaxy at the end of the

southern tail. Hence, when completed we will have full UBVI + H_alpha

coverage (or more for the main galaxy) of four different environments in

the Antennae. In conjunction with the extensive multi- wavelength

database we have collected (both HST and ground based) these

observations will provide answers to fundamental questions such as: How

do these clusters form and evolve? How is star formation triggered? How

do star clusters affect the local and global ISM, and the evolution of

the galaxy as a whole? The Antennae galaxies are the nearest example of

a major disk--disk merger, and hence may represent our best chance for

understanding how mergers form tremendous numbers of clusters and stars,

both in the local universe and during galaxy assembly at high redshift.

STIS/CC/MA 11576

Physical Parameters of the Upper Atmosphere of the Extrasolar Planet

HD209458b

One of the most studied extrasolar planet, HD209458b, has revealed both

its lower and upper atmosphere thanks to HST and Spitzer observatories.

Through transmission spectroscopy technique, several atmospheric species

were detected: NaI, HI, OI and CII. Using STIS archived transit

absorption spectrum from 3000 to 8000 Angstrom, we obtained detailed

constraints on the vertical profile of temperature, pressure and

abundances (Sing et al 2008a, 2008b, Lecavelier et al. 2008b).

By observing in the NUV, from 2300 to 3100 Angstrom, we expect to obtain

new constraints on the physical conditions and the chemical composition

of the upper atmosphere: temperature/pressure profile up to very high in

the atmosphere, abundance and condensation altitudes of new species, and

new insight in the atmospheric escape and ionization state at the upper

levels. The observation of four HD209458b transits with a single E230M

setting will give access to many NUV atomic lines addressing these

issues. The proposed observations will probe, for the first time, in

details the atmosphere of a hot Jupiter, thus bench marking follow up

studies.

STIS/CCD 11567

Boron Abundances in Rapidly Rotating Early-B Stars

Models of rotation in early-B stars predict that rotationally driven

mixing should deplete surface boron abundances during the main-sequence

lifetime of many stars. However, recent work has shown that many boron

depleted stars are intrinsically slow rotators for which models predict

no depletion should have occurred, while observations of nitrogen in

some more rapidly rotating stars show less mixing than the models

predict. Boron can provide unique information on the earliest stages of

mixing in B stars, but previous surveys have been biased towards narrow-

lined stars because of the difficulty in measuring boron abundances in

rapidly rotating stars. The two targets observed as part of our Cycle 13

SNAP program 10175, just before STIS failed, demonstrate that it is

possible to make useful boron abundance measurements for early-B stars

with Vsin(i) above 100 km/s. We propose to extend that survey to a large

enough sample of stars to allow statistically significant tests of

models of rotational mixing in early-B stars.

WFC3/ACS/UVIS 11360

Star Formation in Nearby Galaxies

Star formation is a fundamental astrophysical process; it controls

phenomena ranging from the evolution of galaxies and nucleosynthesis to

the origins of planetary systems and abodes for life. The WFC3,

optimized at both UV and IR wavelengths and equipped with an extensive

array of narrow-band filters, brings unique capabilities to this area of

study. The WFC3 Scientific Oversight Committee (SOC) proposes an

integrated program on star formation in the nearby universe which will

fully exploit these new abilities. Our targets range from the

well-resolved R136 in 30 Dor in the LMC (the nearest super star cluster)

and M82 (the nearest starbursting galaxy) to about half a dozen other

nearby galaxies that sample a wide range of star-formation rates and

environments. Our program consists of broad band multiwavelength imaging

over the entire range from the UV to the near-IR, aimed at studying the

ages and metallicities of stellar populations, revealing young stars

that are still hidden by dust at optical wavelengths, and showing the

integrated properties of star clusters. Narrow-band imaging of the same

environments will allow us to measure star-formation rates, gas

pressure, chemical abundances, extinction, and shock morphologies. The

primary scientific issues to be addressed are: (1) What triggers star

formation? (2) How do the properties of star-forming regions vary among

different types of galaxies and environments of different gas densities

and compositions? (3) How do these different environments affect the

history of star formation? (4) Is the stellar initial mass function

universal or determined by local conditions?

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).

-Lynn               

NASA office: 301-286-2876

__________________________________________________________
Lynn F. Bassford
Hubble Space Telescope
CHAMP Mission Operations Manager
CHAMP Flight Operations Team Manager
Lockheed Martin Mission Services (LMMS)

"...Hubble is the most significant science instrument of all time in terms of its productivity..."     Scott Altman @12:45pm 5/21/9 STS-125 Senate Subcommittee Hearing