NASA Hubble Space Telescope Daily Report #4972

HUBBLE SPACE TELESCOPE DAILY REPORT #4972

Continuing to Collect World Class Science

PERIOD COVERED: 5am November 13 – 5am November 16, 2009 (DOY 317/10:00z-320/10:00z)

OBSERVATIONS SCHEDULED

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/IR 11909

UVIS Hot Pixel Anneal

The on-orbit radiation environment of WFC3 will continually generate new hot pixels. This proposal performs the procedure required for repairing those hot pixels in the UVIS CCDs. During an anneal, the two-stage thermo-electric cooler (TEC) is turned off and the four-stage TEC is used as a heater to bring the UVIS CCDs up to ~20 deg. C. As a result of the CCD warmup, a majority of the hot pixels will be fixed; previous instruments such as WFPC2 and ACS have seen repair rates of about 80%. Internal UVIS exposures are taken before and after each anneal, to allow an assessment of the procedure’s effectiveness in WFC3, provide a check of bias, global dark current, and hot pixel levels, as well as support hysteresis (bowtie) monitoring and CDBS reference file generation. One IR dark is taken after each anneal, to provide a check of the IR detector.

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 3×3 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 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 11897

FUV Spectroscopic Sensitivity Monitoring

The purpose of this proposal is to monitor sensitivity in each FUV grating mode to detect any changes due to contamination or other causes.

ACS/WFC 11881

ACS internal CTE Monitor

The charge transfer efficiency (CTE) of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be closely monitored at regular intervals, because it is likely to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets (lamps) only, so all of the exposures should be taken during Earth occultation time (but not during SAA passages). This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing (program 8948), so that results from each epoch can be directly compared. Extended Pixel Edge Response (EPER) and First Pixel Response (FPR) data will be obtained over a range of signal levels for both the Wide Field Channel (WFC), and the High Resolution Channel (HRC).

ACS/WFC3/WFC 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 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1, and 1×1 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/UV 11801

Black Holes in Globular Clusters

Search for >3000 solar mass black holes at the centers of three Galactic globular clusters using stellar proper motions.

FGS 11789

An Astrometric Calibration of Population II Distance Indicators

In 2002, HST produced a highly precise parallax for RR Lyrae. That measurement resulted in an absolute magnitude, M(V)= 0.61+/-0.11, a useful result, judged by the over ten refereed citations each year since. It is, however, unsatisfactory to have the direct, parallax-based, distance scale of Population II variables based on a single star. We propose, therefore, to obtain the parallaxes of four additional RR Lyrae stars and two Population II Cepheids, or W Vir stars. The Population II Cepheids lie with the RR Lyrae stars on a common K-band Period-Luminosity relation. Using these parallaxes to inform that relationship, we anticipate a zero-point error of 0.04 magnitude. This result should greatly strengthen confidence in the Population II distance scale and increase our understanding of RR Lyrae star and Pop. II Cepheid astrophysics.

WFC3/IR/ACS/WFC 11731

Studying Cepheid Systematics in M81: H-band Observations

The local value of the Hubble Constant remains one of the most important constraints in cosmology, but improving on the 10% accuracy of the HST Key Project is challenging. No improvements will be convincing until the metallicity dependence is well constrained and blending effects are fully understood. M81 and its dwarf companion Holmberg IX are superb laboratories for studying Cepheid systematics because they contain large numbers of bright Cepheids with a good spread in metallicity lying at a common, relatively close distance. We have identified 180 12< P< 70 day Cepheids in these two galaxies using the Large Binocular Telescope (compared to 30 in total by the KP), and will expand the sample further in 2008-2009. We will use 10 orbits with WFC3/IR to obtain H-band images of 100 Cepheids in M81 to add to the ACS/BVI calibrations we will obtain from archival data and 1 orbit with WFC3/UVIS to add B-band data for Holmberg IX. Four band BVIH photometry will allow us to flux calibrate, estimate extinction, measure metallicity effects and then check the results in detail. We can also examine blending effects on WFC3/IR data in a relatively nearby galaxy before it is applied to more distant galaxies. Our M81 sample is three times larger than the next best sample, that of NGC4258, and suffers less from blending because M81 is at half the distance, so it is an excellent laboratory for studying Cepheid systematics even if it lacks as precise a geometric distance as NGC4258. 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/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/UV 11646 Light Echoes as Probes of Supernova Type Ia Environments Environmental factors of Type Ia supernovae are key in understanding their nature, lightcurve evolution, and utility as cosmological standard candles. The progenitor ages (and many other properties) are bimodal, differing by roughly an order of magnitude. Is this reflected as well in the differences in their immediate surroundings in terms of gas and dust? The most powerful and direct way to address this issue is by imaging the reflected light from the dust itself via a light echo. In order for this approach to work, however, one must start imaging the vicinity of the supernova frequently and soon after the explosion is seen. We propose to maintain the imaging sequences crucial for understanding the three-dimensional dust distribution of two recent and key Type Ia supernovae, in a timely manner that will prevent otherwise significant holes in our knowledge. These observations are likely to be important in determining if the interstellar versus the circumstellar environments are more important in determining the appearance of Type Ia explosions, and thereby offer a clue as to the poorly-understood mass-loss history of SN Ia progenitors. STIS/CCD 11611 Are Narrow-Line Seyfert 1 Galaxies Viewed Pole-on? We will obtain spatially resolved spectra of 3 Narrow-Line Seyfert 1 galaxies (NLS1s) with the STIS G430M grating centered on the bright [O III] emission lines. We will measure the radial velocities of the [O III] lines across the narrow-line regions of these AGN and determine the inclinations of their torus/accretion-disk axes via our kinematic models. Our goal is to answer the following question: are NLS1s viewed pole-on? If so, then the narrow widths of their permitted lines may be due to geometric effects, rather than low black hole masses and correspondingly high Eddington ratios as indicated by the currently popular paradigm for NLS1s. STIS/CCD 11606 Dynamical Hypermassive Black Hole Masses We will use STIS spectra to derive the masses of 5 hypermassive black holes (HMBHs). From the observed scaling relations defined by less massive spheroids, these objects are expected to reside at the nuclei of host galaxies with stellar velocity dispersions greater than 320 km/s. These 5 targets have confirmed regular gas distributions on the scales of the black hole sphere of influence. It is essential that the sphere of influence is resolved for accurate determinations of black hole mass (0.1″). These scales cannot be effectively observed from the ground. Only two HMBHs have had their masses modeled so far; it is impossible to draw any general conclusions about the connections between HMBH mass and their massive host galaxies. With these 5 targets we will determine whether these HMBHs deviate from the scaling relations defined by less massive spheroids. A larger sample will allow us to firmly anchor the high mass end of the correlation between black hole mass and stellar velocity dispersion, and other scaling relations. Therefore we are also conducting a SNAPshot program with which we expect to detect a further 24 HMBH candidates for STIS observation in future cycles. At the completion of this project we will have populated the high mass end of the scaling relations with the sample sizes enjoyed by less massive spheroids. ACS/WFC3 11599 Distances of Planetary Nebulae from SNAPshots of Resolved Companions Reliable distances to individual planetary nebulae (PNe) in the Milky Way are needed to advance our understanding of their spatial distribution, birthrates, influence on galactic chemistry, and the luminosities and evolutionary states of their central stars (CSPN). Few PNe have good distances, however. One of the best ways to remedy this problem is to find resolved physical companions to the CSPN and measure their distances by photometric main-sequence fitting. We have previously used HST to identify and measure probable companions to 10 CSPN, based on angular separations and statistical arguments only. We now propose to use HST to re-observe 48 PNe from that program for which additional companions are possibly present. We then can use the added criterion of common proper motion to confirm our original candidate companions and identify new ones in cases that could not confidently be studied before. We will image the region around each CSPN in the V and I bands, and in some cases in the B band. Field stars that appear close to the CSPN by chance will be revealed by their relative proper motion during the 13+ years since our original survey, leaving only genuine physical companions in our improved and enlarged sample. This study will increase the number of Galactic PNe with reliable distances by 50 percent and improve the distances to Pne with previously known companions. WFPC2 11593 Dynamical Masses of the Coolest Brown Dwarfs T dwarfs are excellent laboratories to study the evolution and the atmospheric physics of both brown dwarfs and extrasolar planets. To date, only a single T dwarf binary has a dynamical mass determination, and more are sorely needed. The prospects of measuring more dynamical masses over the next decade are limited to 6 known short-period T dwarf binaries. We propose here to obtain Long-Term HST/ACS monitoring for the 3 of the 6 binaries which cannot be resolved with AO from the ground. Upon completion, our program will substantially increase the number of T dwarf dynamical mass measurements and thereby provide key benchmarks for testing theoretical models of ultracool objects. 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. WFC3/UV 11589 Hypervelocity Stars as Unique Probes of the Galactic Center and Outer Halo We propose to obtain high-resolution images of 11 new hypervelocity stars in the Galactic halo in order to establish the first-epoch astrometric frame, as a part of a long-term program to measure precise proper motions in an absolute inertial frame. The origin of these recently discovered stars with extremely large positive radial velocities, in excess of the escape speed from the Galaxy, is consistent only with being ejected from the deep potential well of the massive black hole at the Galactic center. Reconstructing the full three-dimensional space motion of the hypervelocity stars, through astrometric proper motions, provides a unique opportunity to measure the shape and orientation of the triaxial dark matter halo. The hypervelocity stars allow determination of the Galactic potential out to 120 kpc, independently of and at larger distances than is afforded by tidal streams of satellite galaxies such as the Sagittarius dSph galaxy. Proper motions of the full set of hypervelocity stars will provide unique constraints on massive star formation in the environment of the Galactic center and on the history of stellar ejection by the supermassive black hole. We request one orbit with WFC3 for each of the 11 hypervelocity stars to establish their current positions relative to background galaxies. We request a repeated observation of these stars in Cycle 19, which will conclusively measure the astrometric proper motions. STIS/CCD 11572 Characterizing Atmospheric Sodium in the Transiting hot-Jupiter HD189733b We propose STIS transit observations of the exoplanet HD189733b with the goal of measuring atmospheric atomic sodium. Our strategy is to repeat the observing meathods used for HD209458b, which resulted in a successful exoplanetary atmospheric sodium detection. Initial ground-based measurements suggest that the sodium signature on HD189733 could be up to three times larger than HD209458b, making a robust 8? detection possible within a 12 orbit program observing three transits. Transit transmission spectra resulting from space-based measurements have the advantage of retaining absolute transit depths when features are measured, which will make it possible to provide an observational link between sodium and atmospheric haze detected with ACS. Such a link can break modeling degeneracies and providing stringent constraints on the overall atmospheric properties, making such atmospheric information as abundances and the temperature-pressure-altitude relation known. A successful measurement will also allow for comparative atmospheric exoplanetology, as an atmospheric feature will be measured with the same instrument in two separate planets. WFC3/UVIS 11565 A Search for Astrometric Companions to Very Low-Mass, Population II Stars We propose to carry out a Snapshot search for astrometric companions in a subsample of very low-mass, halo subdwarfs identified within 120 parsecs of the Sun. These ultra-cool M subdwarfs are local representatives of the lowest-mass H burning objects from the Galactic Population II. The expected 3-4 astrometric doubles that will be discovered will be invaluable in that they will be the first systems from which gravitational masses of metal-poor stars at the bottom of the main sequence can be directly measured. WFC3/ACS/IR 11563 Galaxies at z~7-10 in the Reionization Epoch: Luminosity Functions to <0.2L* from Deep IR Imaging of the HUDF and HUDF05 Fields The first generations of galaxies were assembled around redshifts z~7-10+, just 500-800 Myr after recombination, in the heart of the reionization of the universe. We know very little about galaxies in this period. Despite great effort with HST and other telescopes, less than ~15 galaxies have been reliably detected so far at z>7, contrasting with the ~1000 galaxies detected to date at z~6, just 200-400 Myr later, near the end of the reionization epoch. WFC3 IR can dramatically change this situation, enabling derivation of the galaxy luminosity function and its shape at z~7-8 to well below L*, measurement of the UV luminosity density at z~7-8 and z~8-9, and estimates of the contribution of galaxies to reionization at these epochs, as well as characterization of their properties (sizes, structure, colors). A quantitative leap in our understanding of early galaxies, and the timescales of their buildup, requires a total sample of ~100 galaxies at z~7-8 to ~29 AB mag. We can achieve this with 192 WFC3 IR orbits on three disjoint fields (minimizing cosmic variance): the HUDF and the two nearby deep fields of the HUDF05. Our program uses three WFC3 IR filters, and leverages over 600 orbits of existing ACS data, to identify, with low contamination, a large sample of over 100 objects at z~7-8, a very useful sample of ~23 at z~8-9, and limits at z~10. By careful placement of the WFC3 IR and parallel ACS pointings, we also enhance the optical ACS imaging on the HUDF and a HUDF05 field. We stress (1) the need to go deep, which is paramount to define L*, the shape, and the slope alpha of the luminosity function (LF) at these high redshifts; and (2) the far superior performance of our strategy, compared with the use of strong lensing clusters, in detecting significant samples of faint z~7-8 galaxies to derive their luminosity function and UV ionizing flux. Our recent z~7.4 NICMOS results show that wide-area IR surveys, even of GOODS-like depth, simply do not reach faint enough at z~7-9 to meet the LF and UV flux objectives. In the spirit of the HDF and the HUDF, we will waive any proprietary period, and will also deliver the reduced data to STScI. The proposed data will provide a Legacy resource of great value for a wide range of archival science investigations of galaxies at redshifts z~2-9. The data are likely to remain the deepest IR/optical images until JWST is launched, and will provide sources for spectroscopic followup by JWST, ALMA and EVLA.

WFC3/UVI/IR 11557

The Nature of Low-Ionization BAL QSOs

The rare subclass of optically-selected QSOs known as low-ionization broad absorption line (LoBAL) QSOs show signs of high-velocity gas outflows and reddened continua indicative of dust obscuration. Recent studies show that galaxies hosting LoBAL QSOs tend to be ultraluminous infrared systems that are undergoing mergers, and that have dominant young (< 100 Myr) stellar populations. Such studies support the idea that LoBAL QSOs represent a short- lived phase early in the life of QSOs, when powerful AGN-driven winds are blowing away the dust and gas surrounding the QSO. If so, understanding LoBALs would be critical in the study of phenomena regulating black hole and galaxy evolution, such as AGN feedback and the early stages of nuclear accretion. These results, however, come from very small samples that may have serious selection biases. We are therefore taking a more aggressive approach by conducting a systematic multiwavelength study of a volume limited sample of LoBAL QSOs at 0.5 < z < 0.6 drawn from SDSS. We propose to image their host galaxies in two bands using WFC3/UVIS and WFC3/IR to study the morphologies for signs of recent tidal interactions and to map their interaction and star forming histories. We will thus determine whether LoBAL QSOs are truly exclusively found in young merging systems that are likely to be in the early stages of nuclear accretion. 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 11522 COS-GTO: STAR FORMATION/LYMAN-ALPHA A sample of 20 star-forming galaxies will be observed with COS G130M. The galaxies were selected from the Kitt Peak International Spectroscopic Survey (KISSR) data release and cover a broad range of luminosity, oxygen abundance, and reddening. The goal of the program is to characterize the Lyman-alpha properties and establish correlations with fundamental galaxy properties. Each galaxy will be observed for one orbit. 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).

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.)

HSTARS:

12072 – GSAcq(2,1,1) results in fine lock backup (2,0,2) using FGS-2 @ 318/21:25:56z

Observations possibly affected: WFC3 187 – 191 Proposal ID# 11548

12074 – GSAcq(1,2,1) fails during LOS due to scan step exceeded @ 320/07:59z

Observations affected: ACS 5-8, Proposal ID# 11879; STIS 3, Proposal ID# 10897; and COS 2 Proposal ID# 11895

COMPLETED OPS REQUEST:

18758-0 – NCS CPL from Standby to Pressure Prime @ 317/1558z

COMPLETED OPS NOTES: (None)

                        SCHEDULED      SUCCESSFUL

FGS GSAcq               32                   31

FGS REAcq               19                   19

OBAD with Maneuver      15                   15

SIGNIFICANT EVENTS: (None)