HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT      # 4603

PERIOD COVERED: 5am May 02 - 5am May 05, 2008 (DOY 123/0900z - 126/0900z)  

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA calibration - CR Persistence Part 6

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

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

contour 23, and every time a NICMOS exposure is scheduled within 50

minutes of coming out of the SAA. The darks will be obtained in parallel

in all three NICMOS Cameras. The POST-SAA darks will be non-standard

reference files available to users with a USEAFTER date/time mark. The

keyword 'USEAFTER=date/time' will also be added to the header of each

POST-SAA DARK frame. The keyword must be populated with the time, in

addition to the date, because HST crosses the SAA ~8 times per day so

each POST-SAA DARK will need to have the appropriate time specified, for

users to identify the ones they need. Both the raw and processed images

will be archived as POST-SAA DARKSs. Generally we expect that all NICMOS

science/calibration observations started within 50 minutes of leaving an

SAA will need such maps to remove the CR persistence from the science i

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

passages leave different imprints on the NICMOS detectors.

NIC 11495

The first direct detection of an extrasolar planetary stratosphere?

We request NICMOS grism spectroscopy to observe the transit of WASP-3b.

This newly discovered planet is the hottest nearby planet discovered so

far. The atmosphere is predicted to be so hot that TiO and VO remain in

the gas phase, creating a hot, strongly absorbing stratosphere. This

molecular absorption will cause a 6% enhancement in the transit depth at

0.8 microns, compared to that at 1.3 microns. NICMOS/G096 and

NICMOS/G141 observations will therefore provide a straightforward test

of the hot stratosphere hypothesis. The HST observations will provide a

precisely determined radius measurement. This is required to drive

advances in theories of planetary formation, evolution, and atmospheric

physics and chemistry. The atmospheric TiO and VO absorption is

predicted to cause an anomalously high IR brightness temperature for the

planet. We need HST's direct test of the hot stratosphere hypothesis

promptly to enable appropriate cold-Spitzer observations to be planned

and interpreted. Spitzer is likely to exhaust its cryogens before these

observations could be scheduled via the cycle 17 GO process.

NIC1/NIC2/NIC3 11321

NICMOS Cycle 16 Flats Stability

This calibration proposal is the Cycle 16 NICMOS flat field monitor

program. A series of camera 1, 2, & 3 flat fields will be obtained to

monitor the health of the cameras.

FGS 11213

Distances to Eclipsing M Dwarf Binaries

We propose HST FGS observations to measure accurate distances of 5

nearby M dwarf eclipsing binary systems, from which model-independent

luminosities can be calculated. These objects have either poor or no

existing parallax measurements. FGS parallax determinations for these

systems, with their existing dynamic masses determined to better than

0.5%, would serve as model-independent anchor points for the low-mass

end of the mass-luminosity diagram.

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!

NIC2/WFPC2 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. {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}.

NIC1 11117

The Search for Atmospheric Water in the Transiting Planet HD189733b

We propose to use the NICMOS camera to search for transit NIR signatures

of atmospheric water in HD189733b. While water absorption bands exist in

the optical and IR, space-based NIR signatures are uniquely positioned

to offer the best chance at detection. Using narrow band photometric

filters, we will be able to detect absorption signatures while the

planet is in primary transit. A positive detection would be the first

proof of water on an extrasolar planet. Furthermore, it would provide

invaluable planetary information, constraining the entire chemistry. As

a byproduct of the high SNR required for our primary science goal, we

will be able to improve on the value of the planetary radius, a result

independent of our primary science objective. The accurate radius

estimate, together with planet structure models, will allow constraining

the planet interior and its relationship with formation models and

stellar metallicity.

NIC3 11107

Imaging of Local Lyman Break Galaxy Analogs: New Clues to Galaxy

Formation in the Early Universe

We have used the ultraviolet all-sky imaging survey currently being

conducted by the Galaxy Evolution Explorer {GALEX} to identify for the

first time a rare population of low-redshift starbursts with properties

remarkably similar to high-redshift Lyman Break Galaxies {LBGs}. These

"compact UV luminous galaxies" {UVLGs} resemble LBGs in terms of size,

SFR, surface brightness, mass, metallicity, kinematics, dust, and color.

The UVLG sample offers the unique opportunity of investigating some very

important properties of LBGs that have remained virtually inaccessible

at high redshift: their morphology and the mechanism that drives their

star formation. Therefore, in Cycle 15 we have imaged 7 UVLGs using ACS

in order to 1} characterize their morphology and look for signs of

interactions and mergers, and 2} probe their star formation histories

over a variety of timescales. The images show a striking trend of small-

scale mergers turning large amounts of gas into vigorous starbursts {a

process referred to as dissipational or "wet" merging}. Here, we propose

to complete our sample of 31 LBG analogs using the ACS/SBC F150LP {FUV}

and WFPC2 F606W {R} filters in order to create a statistical sample to

study the mechanism that triggers star formation in UVLGs and its

implications for the nature of LBGs. Specifically, we will 1} study the

trend between galaxy merging and SFR in UVLGs, 2} artificially redshift

the FUV images to z=1-4 and compare morphologies with those in similarly

sized samples of LBGs at the same rest-frame wavelengths in e.g. GOODS,

UDF, and COSMOS, 3} determine the presence and morphology of significant

stellar mass in "pre- burst" stars, and 4} study their immediate

environment. Together with our Spitzer {IRAC+MIPS}, GALEX, SDSS and

radio data, the HST observations will form a unique union of data that

may for the first time shed light on how the earliest major episodes of

star formation in high redshift galaxies came about. This proposal was

adapted from an ACS HRC+WFC proposal to meet the new Cycle 16 observing

constraints, and can be carried out using the ACS/SBC and WFPC2 without

compromising our original science goals.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

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

HSTARS: (None)

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

                       SCHEDULED      SUCCESSFUL 

FGS GSacq               26                 26                  

FGS REacq               15                 15                  

OBAD with Maneuver 82                 81                    

SIGNIFICANT EVENTS: (None)