This week on HST


HST Programs: June 13, 2011 - June 19, 2011

Program Number Principal Investigator Program Title
11568 Seth Redfield, Wesleyan University A SNAPSHOT Survey of the Local Interstellar Medium: New NUV Observations of Stars with Archived FUV Observations
11714 Howard E. Bond, Space Telescope Science Institute Snapshot Survey for Planetary Nebulae in Local Group Globular Clusters
11728 Timothy M. Heckman, The Johns Hopkins University The Impact of Starbursts on the Gaseous Halos of Galaxies
12027 James C. Green, University of Colorado at Boulder COS-GTO: STAR FORMATION/LYMAN-ALPHA Part 2
12029 James C. Green, University of Colorado at Boulder WARM AND HOT ISM IN AND NEAR THE MILKY WAY Part 2
12060 Sandra M. Faber, University of California - Santa Cruz Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey -- GOODS-South Field, Non-SNe-Searched Visits
12061 Sandra M. Faber, University of California - Santa Cruz Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey -- GOODS-South Field, Early Visits of SNe Search
12099 Adam Riess, The Johns Hopkins University Supernova Follow-up for MCT
12104 Marc Postman, Space Telescope Science Institute Through a Lens, Darkly - New Constraints on the Fundamental Components of the Cosmos
12166 Harald Ebeling, University of Hawaii A Snapshot Survey of The Most Massive Clusters of Galaxies
12173 Claus Leitherer, Space Telescope Science Institute Feedback between Stars, ISM and IGM in IR-Luminous Galaxies
12177 Pieter van Dokkum, Yale University 3D-HST: A Spectroscopic Galaxy Evolution Treasury
12185 Jenny E. Greene, University of Texas at Austin The Hosts of Megamaser Disk Galaxies
12192 James T. Lauroesch, University of Louisville Research Foundation, Inc. A SNAPSHOT Survey of Interstellar Absorption Lines
12197 Johan Richard, Centre de Recherche Astronomique de Lyon Evolution in the Size-Luminosity Relation of HII regions in Gravitationally-lensed galaxies
12206 Mark S. Westmoquette, University College London (UCL) Starburst-driven shocks and feedback in the near-IR at high resolution
12208 John J. Bochanski, The Pennsylvania State University Resolving Disks and Jets in a New, Benchmark Low-Mass Binary
12209 Adam S. Bolton, University of Utah A Strong Lensing Measurement of the Evolution of Mass Structure in Giant Elliptical Galaxies
12210 Adam S. Bolton, University of Utah SLACS for the Masses: Extending Strong Lensing to Lower Masses and Smaller Radii
12212 D. Michael Crenshaw, Georgia State University Research Foundation What are the Locations and Kinematics of Mass Outflows in AGN?
12236 Lisa Glass, Dominion Astrophysical Observatory The Nuclear to Global Connection: a Detailed View of Compact Stellar Nuclei in a Complete Sample of Virgo Ellipticals
12238 William E. Harris, McMaster University Supermassive Star Clusters in Supergiant Galaxies: Tracing the Enrichment of the Earliest Stellar Systems
12248 Jason Tumlinson, Space Telescope Science Institute How Dwarf Galaxies Got That Way: Mapping Multiphase Gaseous Halos and Galactic Winds Below L*
12264 Simon L. Morris, University of Durham The Relationship between Gas and Galaxies for 0
12269 Claudia Scarlata, University of Minnesota - Twin Cities The escape of Lya photons in star-forming galaxies
12283 Matthew A. Malkan, University of California - Los Angeles WFC3 Infrared Spectroscopic Parallel Survey {WISP}: A Survey of Star Formation Across Cosmic Time
12286 Hao-Jing Yan, University of Missouri - Columbia Hubble Infrared Pure Parallel Imaging Extragalactic Survey {HIPPIES}
12287 Scott D. Friedman, Space Telescope Science Institute Constraining Models of Deuterium Depletion and Galactic Chemical Evolution with Improved Measurements of D/H
12289 J. Christopher Howk, University of Notre Dame A COS Snapshot Survey for z < 1.25 Lyman Limit Systems
12302 Edward F. Guinan, Villanova University Probing the Atmospheres of Cepheids with HST-COS: Pulsation Dependences, Plasma Dynamics and Heating Mechanisms
12320 Brian Chaboyer, Dartmouth College The Ages of Globular Clusters and the Population II Distance Scale
12324 C. S. Kochanek, The Ohio State University The Temperature Profiles of Quasar Accretion Disks
12328 Pieter van Dokkum, Yale University 3D-HST: A Spectroscopic Galaxy Evolution Treasury Part 2

Selected highlights

GO 11728: The Impact of Starbursts on the Gaseous Halos of Galaxies

A computer simulation of galactic gas accretion and outflow The detailed history of galaxy formation and assembly depends on the availability of gas for star formation, and on how processes engendered by that star formation affects the distribution and intrinsic properties of that gas. In particular, feedback in the form of winds and ionising radiation from either young stellar associations or massive black holes may be capable of interfering with, and even interrupting, the overall assembly process. The present program aims to investigate this issue by probing the nature of halo gas in the vicinity of galaxies that have undergone recent (<100 Myr old) starbursts. The halo gas is expected to reside predominantly at high temperatures. The most effective means of detecting such gas is through ultraviolet spectroscopy, where gas within nearby systems can be detected as absorption lines superimposed on the spectra of more distant objects, usually quasars. The present program is using the Cosmic Origins Spectrograph to observe moderate-redshift QSOs that lie at small angular separations from the starburst galaxies. The sightlines run through the halos of the galaxies, and the QSOs therefore provide a pencilbeam backlight that probes hot gas in the foreground systems.

GO 12099: Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey - SNe follow-up

High redshift supernovae from HST observations in previous cycles CANDELS is one of three Multi-Cycle Treasury Program, whose observations will be executed over the next three HST Cycles. It builds on past investment of both space- and ground-based observational resources. In particular, it includes coverage of the two fields of the Great Observatory Origins Deep Survey (GOODS), centred on the northern Hubble Deep Field (HDF) in Ursa Major and the Chandra Deep Field-South in Fornax. In addition to deep HST data at optical and near-infrared wavelengths, the fields have been covered at X-ray wavelengths by Chandra (obviously) and XMM-Newton; at mid-infrared wavelengths with Spitzer; and ground-based imaging and spectroscopy using numerous telescopes, including the Kecks, Surbaru and the ESO VLT. This represents an accumulation of almost 1,000 orbits of HST time, and comparable scale allocations on Chandra, Spitzer and ground-based facilities. The CANDELS program is capitalising on this large investment, with new observations with WFC3 and ACS on both GOODS fields, and on three other fields within the COSMOS, EGS and UDS survey areas (see this link for more details). The prime aims of the program are twofold: reconstructing the history of galaxy formation, star formation and nuclear galactic activity at redshifts between z=8 and z=1.5; and searching for high-redshift supernovae to measure their properties at redshifts between z~1 and z~2. The program incorporates a tiered set of observations that complement, in areal coverage and depth, the deep UDF observations, while the timing of individual observations will be set to permit detection of high redshift SNe candidates, for subsequent separate follow-up. The present observations target a high-redshift supernova identified in the course of the survey imaging.

GO 12208: Resolving Disks and Jets in a New, Benchmark Low-Mass Binary

Artist's impression of activity within a disk in a member of the TW Hya association The T Tauri stage of evolution occurs early in a star's lifetime, within ~10 Myrs of its birth, when it still retains a dense, dust and gas-rich circumstellar disk. During this phase, there is substantial accretion of material onto the central star. This leads to heating of the inner regions of the accretion disk, and significant emission at ultraviolet and X-ray wavelengths. These phenomena have been studied extensively for solar-type stars, corresponding to end-point masses from around 0.5 MSun to ~2 MSun. However, less observational information exists for lower mass stars and brown dwarfs. The present program targets two recently discovered members of the sparse TW Hydrae Association, TWA 30A and 30B. The primary star in this wide (3400 AU separation) binary is mid-type M dwarf (spectral type M5), which marks itself as unusual through the presence of strong emission lines due to forbidden transitions in atomic and ionised oxygen and sulphur. These indicate that this is an extremely young object, where significant gas content remains in the accretion disk. For an age of ~7 Myrs, the mass is only ~0.12 MSun. TWA 30B, discovered only last year, has a similar spectral type and similar emission lines, but is 5 magnitudes fainter than TWA 30A in the K-band. This strongly suggests that we are viewing this stellar system edge-on, and the reduced brightness reflects absorption within the dusty circumstellar disk. The present HST observations aim to use narrowband imaging with WFC3 to probe the physical characteristics of the disks in these young, low-mass systems.

GO 12248: How Dwarf Galaxies Got That Way: Mapping Multiphase Gaseous Halos and Galactic Winds Below L*

A computer simulation of galactic gas accretion and outflow Galaxy formation, and star formation within a galaxy, requires the presence of gas. The detailed evolution of individual galactic systems therefore depends on how gas is accreted, recycled, circulated through the halo and, perhaps, ejected back into the intergalactic medium. Tracing that evolutionary history is difficult, since gas passes through many different phases, some of which are easier to detect than others. During accretion and, probably, subsequent recycling, the gas is expected to be reside predominantly at high temperatures. The most effective means of detecting such gas is through ultraviolet spectroscopy, where gas within nearby systems can be detected as absorption lines superimposed on the spectra of more distant objects, usually quasars. The present program is using the Cosmic Origins Spectrograph to observe low- to moderate redshift QSOs (0.1 < z < 1) that lie at small angular separations from sub-L* mass galaxies (0.02 < M/L* < 0.3) at redshifts between z=0.01 and 0.06. The sightlines run through the halos of the galaxies, and the QSOs therefore provide a pencilbeam backlight that probes hot gas in the foreground systems.

Past weeks:
page by Neill Reid, updated 2/5/2011