| Program Number | Principal Investigator | Program Title |
|---|---|---|
| 13297 | Giampaolo Piotto, Universita degli Studi di Padova | The HST Legacy Survey of Galactic Globular Clusters: Shedding UV Light on Their Populations and Formation |
| 13643 | Gaspard Duchene, University of California - Berkeley | Imaging the tenuous dusty atmosphere of edge-on protoplanetary disks |
| 13647 | Ryan Foley, University of Illinois at Urbana - Champaign | Testing the Standardizability of Type Ia Supernovae with the Cepheid Distance of a Twin Supernova |
| 13650 | Kevin France, University of Colorado at Boulder | The MUSCLES Treasury Survey: Measurements of the Ultraviolet Spectral Characteristics of Low-mass Exoplanetary Systems |
| 13654 | Matthew Hayes, Stockholm University | Ultraviolet Spectroscopy of the Extended Lyman Alpha Reference Sample |
| 13667 | Marc W. Buie, Southwest Research Institute | Observations of the Pluto System During the New Horizons Encounter Epoch |
| 13671 | Harald Ebeling, University of Hawaii | Beyond MACS: A Snapshot Survey of the Most Massive Clusters of Galaxies at z>0.5 |
| 13677 | Saul Perlmutter, University of California - Berkeley | See Change: Testing time-varying dark energy with z>1 supernovae and their massive cluster hosts |
| 13688 | Marco Castellano, INAF, Osservatorio Astronomico di Roma | A clear patch in the dark age Universe? Looking for reionization sources around two bright Ly-alpha emitting galaxies at z=7 |
| 13689 | Aleksandar M. Diamond-Stanic, University of Wisconsin - Madison | How Compact is the Stellar Mass in Eddington-Limited Starbursts? |
| 13690 | Tanio Diaz-Santos, Universidad Diego Portales | Tracking the Obscured Star Formation Along the Complete Evolutionary Merger Sequence of LIRGs |
| 13692 | William M. Grundy, Lowell Observatory | Orbits and Physical Properties of Four Binary Transneptunian Objects |
| 13695 | Benne W. Holwerda, Sterrewacht Leiden | STarlight Absorption Reduction through a Survey of Multiple Occulting Galaxies (STARSMOG) |
| 13702 | Sally Oey, University of Michigan | Mapping the LyC-Emitting Regions of Local Galaxies |
| 13713 | Bruno Sicardy, Observatoire de Paris | Observation of Chariklo's rings |
| 13716 | David E. Trilling, Northern Arizona University | Constraining the history of the outer Solar System: Definitive proof with HST |
| 13725 | Paul Kalas, University of California - Berkeley | Testing the correlation between low mass planets and debris disks |
| 13735 | David J. Sand, Texas Tech University | A New Dwarf Galaxy Associated with an Ultra-Compact High Velocity Cloud |
| 13741 | Thaisa Storchi-Bergmann, Universidade Federal do Rio Grande do Sul | Constraining the structure of the Narrow-Line Region of nearby QSO2s |
| 13750 | John M. Cannon, Macalester College | Fundamental Parameters of the SHIELD II Galaxies |
| 13767 | Michele Trenti, University of Melbourne | Bright Galaxies at Hubble's Detection Frontier: The redshift z~9-10 BoRG pure-parallel survey |
| 13776 | Michael D. Gregg, University of California - Davis | Completing The Next Generation Spectral Library |
| 13778 | Edward B. Jenkins, Princeton University | Using ISM abundances in the SMC to Correct for Element Depletions by Dust in QSO Absorption Line Systems |
| 13779 | Sangeeta Malhotra, Arizona State University | The Faint Infrared Grism Survey (FIGS) |
| 13782 | Dan Milisavljevic, Smithsonian Institution Astrophysical Observatory | The Double Supernova in NGC 6984 |
| 13786 | Glenn Schneider, University of Arizona | Decoding Debris System Substructures: Imprints of Planets/Planetesimals and Signatures of Extrinsic Influences on Material in Ring-Like Disks |
| 13834 | Roeland P. van der Marel, Space Telescope Science Institute | The Proper Motion Field along the Magellanic Bridge: a New Probe of the LMC-SMC interaction |
| 13846 | Todd Tripp, University of Massachusetts - Amherst | The COS Absorption Survey of Baryon Harbors (CASBaH): Probing the Circumgalactic Media of Galaxies from z = 0 to z = 1.5 |
| 13852 | Rongmon Bordoloi, Massachusetts Institute of Technology | How Galaxy Mergers Affect Their Environment: Mapping the Multiphase Circumgalactic Medium of Close Kinematic Pairs |
| 13856 | Denija Crnojevic, Texas Tech University | Resolving the faint end of the satellite luminosity function for the nearest elliptical Centaurus A |
| 13862 | Timothy M. Heckman, The Johns Hopkins University | Measuring the Impact of Starbursts on the Circum-Galactic Medium |
| 13928 | Adam Riess, The Johns Hopkins University | HST and Gaia, Light and Distance |
| 13949 | Andrew J. Levan, The University of Warwick | A Chandra/HST survey of dark gamma-ray bursts |
| 14051 | Jacqueline Radigan, Space Telescope Science Institute | Constraining Dust Hazes at the L/T Transition via Variability |
GO 13677: See Change: Testing time-varying dark energy with z>1 supernovae and their massive cluster hosts
HST/ACS images of a supernova in a galazy at z=1.2 |
The last few years of the twentieth century saw a revolution in cosmology, with the measurement of the acceleration term in expansion at high redshifts and the identification of dark energy as a major cosmological component. The overall significance of this result has been recognised through the award of the Nobel prize and, most recently, the Fundamental Physics Breakthrough Prize to Perlmutter, Riess and Schmidt and their respective teams. Type Ia supernovae are the prime yardstick for measuring the rate of expansion at moderate and high redshifts. The seminal work in this field was carried out with ground-based telescopes, but Hubble offers almost the only way of obtaining reliable post-maximum photometry of these objects to determine the full shape of the light curve. Many previous HST supernovae programs have concentrated on field galaxies, but applying appropriate corrections for in situ reddening by dust remains an issue in these systems, while the overall SNe detection rates are relatively low at high redshifts. The present program takes a different tack, and aims to minimise the uncertainties by searching for supernovae in massive, high-redshift clusters. The expectation is that the majority of detections lie within dust-poor elliptical galaxies; moreover, supernova rates may be higher. The program will obtain ACS observations of ten of the most massive galaxy clusters lying at redshifts 1.1 < z < 1.75. |
GO 13692: Orbits and Physical Properties of Four Binary Transneptunian Objects
Preliminary orbital determination for the KBO WW31, based on C. Veillet's analysis of CFHT observations; the linked image shows the improved orbital derivation, following the addition of HST imaging |
The Kuiper Belt consists of icy planetoids that orbit the Sun within a broad band stretching from Neptune's orbit (~30 AU) to distance sof ~50 AU from the Sun (see David Jewitt's Kuiper Belt page for details). Over 500 KBOs (or trans-Neptunian objects, TNOs) are currently known out of a population of perhaps 70,000 objects with diameters exceeding 100 km. Approximately 2% of the known KBOs are binary (including Pluto, one of the largest known KBOs, regardless of whether one considers it a planet or not). This is a surprisingly high fraction, given the difficulties involved in forming such systems and the relative ease with which they can be disrupted. It remains unclear whether these systems formed from single KBOs (through collisions or 3-body interactions) as the Kuiper Belt and the Solar System have evolved, or whether they represent the final tail of an initial (much larger) population of primordial binaries. These issues can be addressed, at least in part, through deriving a better understanding of the composition of KBOs - and those properties can be deduced by measuring the orbital parameters for binary systems. The present proposal aims to use HST WFC3 observations to map the orbits of four binary systems. Those observations will be ued to determine the orbital period and semi-major axis and the total system mass, while the mid-infrared properties (measured by Spitzer) allow an assessment of the surface area/diameters; combining these measurements gives an estimate of the mean density. |
GO 13834: The Proper Motion Field along the Magellanic Bridge: a New Probe of the LMC-SMC interaction
The Large Magellanic Cloud (upper left) with the Small Magellanic Cloud (right) and the (foreground) Galactic globular cluster47 Tucanae |
The Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are the most massive satellites of the Milky Way galaxy. The orbital motions of these systems can be used to probe the mass distribution of Milky Way, and backtracking the orbits can shed light on how the three systems have interacted, In particular, the well known Magellanic Stream, stretching between the two Clouds, is thought to be a product either of interactions between the Clouds, or of ram-stripping of gas from the LMC on its last passage through the Plane of the Milky Way. Understanding the full scope of the interactions demands knowledge of the tangential motions of these systems - that is, proper motion measurements. Given the distances of the Clouds (~50 kpc.), the actual motions amount to only a few milliarcseconds, but the high spatial resolution and high stability of HST imaging makes such measurements possible. Past observing programs (eg GO 11730) have concentrated on the LMC, using the now-defunct ACS High Resolution Camera (ACS/HRC), the Planetary Camera on WFPC2 and the UVIS camera on WFC3 to target known QSOs lying behind the Clouds; the QSOs serve as fixed reference points for absolute astrometry of the numerous foreground LMC/SMC stars. A recent Cycle 21 program focused on the SMC, targeting 30 newly identified background QSos for WFC3 observations over a two-year period. The present program expands observations to several fields along the Magellanic bridge, a complex of gas and stars that conencts the two clouds, and will test the hypothsesis that the clouds are undergoing their first interaction with teh Milky Way. |
GO 14051: Constraining Dust Hazes at the L/T Transition via Variability
An artist's rendition of brown dwarf atmospheric structure |
Brown dwarfs are failed stars - objects that form like stars, by gravitational collapse within giant molecular clouds, but which have insufficient mass to raise the central temperature above 107 K, and which therefore are unable to ignite hydrogran fusion and maintain a long-lived central energy source. As such, these objects reach a maximum surface temperature of perhaps 3,000K some tens of millions of years after their formation, and subsequently cool and fade into oblivion. As they cool, they move through spectral types M, L and T, with the oldest brown dwarfs now likely to have temperatures close to 300K and emergent spectra characterised by water and ammonia bands, the putative signatures of the spectral class Y. As these dwarfs cool from L to T (~1500 to ~1200K), the atmospheres undergo significant changes, with heavier elements condensing to form dust. That dust can form clouds, perhaps giving the dwarf's surface a banded appearance, similar to Jupiter. The clouds themselves may appear and disappear over relatively short timescales, leading to photometric variations at particular wavelengths. Past programs have used both Spitzer and HST to monitor spectral variability in a number of systems, primarily objects with spectral types in the L/T transition zone. The present program focuses on a single T2 dwarf, SIMP 1629+03, a known spectral variable. Unlike most dwarfs, the known variability appears to show little dependence on wavelength, probably reflecting the presence of high-level dust particles. The present program will use coordinated Spitzer and HST WFC3 IR grism observations to map the variability from 1 to 5 microns over 2 rotation periods, and hence constrain the likely size of the atmospheric dust grains. |