| Program Number | Principal Investigator | Program Title |
|---|---|---|
| 13646 | Ryan Foley, University of Illinois at Urbana - Champaign | Understanding the Progenitor Systems, Explosion Mechanisms, and Cosmological Utility of Type Ia Supernovae |
| 13711 | Abhijit Saha, National Optical Astronomy Observatory, AURA | Establishing a Network of Next Generation SED standards with DA White Dwarfs |
| 13765 | Bradley M Peterson, The Ohio State University | A Cepheid-Based Distance to the Benchmark AGN NGC 4151 |
| 13856 | Denija Crnojevic, Texas Tech University | Resolving the faint end of the satellite luminosity function for the nearest elliptical Centaurus A |
| 14038 | Jennifer Lotz, Space Telescope Science Institute | HST Frontier Fields - Observations of Abell 370 |
| 14059 | Roberto Soria, Curtin University | State transitions of the ULX in M83 |
| 14071 | Sanchayeeta Borthakur, The Johns Hopkins University | How are HI Disks Fed? Probing Condensation at the Disk-Halo Interface |
| 14076 | Boris T. Gaensicke, The University of Warwick | An HST legacy ultraviolet spectroscopic survey of the 13pc white dwarf sample |
| 14077 | Boris T. Gaensicke, The University of Warwick | The frequency and chemical composition of rocky planetary debris around young white dwarfs: Plugging the last gaps |
| 14095 | Gabriel Brammer, Space Telescope Science Institute - ESA | Calibrating the Dusty Cosmos: Extinction Maps of Nearby Galaxies |
| 14098 | Harald Ebeling, University of Hawaii | Beyond MACS: A Snapshot Survey of the Most Massive Clusters of Galaxies at z>0.5 |
| 14119 | Luciana C. Bianchi, The Johns Hopkins University | Understanding Stellar Evolution of Intermediate-Mass Stars from a New Sample of SiriusB-Like Binaries |
| 14120 | Jarle Brinchmann, Universiteit Leiden | He II emission as a tracer of ultra-low metallicity and massive star evolution |
| 14126 | Zachary Edwards, Louisiana State University and A & M College | Startlingly fast evolution of the Stingray Nebula |
| 14127 | Michele Fumagalli, Durham Univ. | First Measurement of the Small Scale Structure of Circumgalactic Gas via Grism Spectra of Close Quasar Pairs |
| 14141 | Guy Worthey, Washington State University | NGSL Extension 1. Hot Stars and Evolved Stars |
| 14149 | Alex V. Filippenko, University of California - Berkeley | Continuing a Snapshot Survey of the Sites of Recent, Nearby Supernovae |
| 14178 | Matthew A. Malkan, University of California - Los Angeles | WFC3 Infrared Spectroscopic Parallel Survey: The WISP Deep Fields |
| 14185 | Ran Wang, Peking University | Imaging the extended star formation in the host galaxy of a millimeter bright quasar at z=6.13ii |
| 14193 | Catherine Espaillat, Boston University | Footprints of the Magnetosphere: the Star- Disk Connection in T Tauri Stars |
| 14206 | Adam Riess, The Johns Hopkins University | A New Threshold of Precision, 30 micro-arcsecond Parallaxes and Beyond |
| 14212 | Karl Stapelfeldt, NASA Goddard Space Flight Center | A Snapshot Imaging Survey of Spitzer-selected Young Stellar Objects in Nearby Star Formation Regions*.t23 |
| 14227 | Casey Papovich, Texas A & M University | The CANDELS Lyman-alpha Emission At Reionization (CLEAR) Experiment |
| 14230 | Jane R. Rigby, NASA Goddard Space Flight Center | The Ultimate Emission Line Diagnostics Study at z=1.4 |
| 14249 | Roberto Mignani, INAF, Istituto di Astrofisica Spaziale e Fisica | The old pulsar PSR J0108-1431, a key target to understand the long-term evolution of neutron stars |
| 14256 | John A. Biretta, Eureka Scientific Inc. | High-Precision Proper Motions in the M87 Jet |
| 14260 | Drake Deming, University of Maryland | A Metallicity and Cloud Survey of Exoplanetary Atmospheres Prior to JWST |
| 14262 | Knud Jahnke, Max-Planck-Institut fur Astronomie, Heidelberg | Are the fastest growing black holes at z=2 caused by major galaxy mergers? |
| 14268 | Nicolas Lehner, University of Notre Dame | Project AMIGA: Mapping the Circumgalactic Medium of Andromeda |
| 14327 | Saul Perlmutter, University of California - Berkeley | See Change: Testing time-varying dark energy with z>1 supernovae and their massive cluster hosts |
| 14329 | Martin C. Weisskopf, NASA Marshall Space Flight Center | Joint Chandra and HST Monitoring and Studies of the Crab Nebula |
| 14341 | Thomas R. Ayres, University of Colorado at Boulder | Alpha Centauri at a Crossroads |
| 14463 | Bruce McCollum, American University | Identifying the Progenitor of a New Red Transient |
| 14470 | Boris T. Gaensicke, The University of Warwick | AR Sco: the first white dwarf pulsar? |
GO 13646: Understanding the Progenitor Systems, Explosion Mechanisms, and Cosmological Utility of Type Ia Supernovae
Supernova 2015F in NGC 2442; image by STan Howerton |
Supernovae are the most spectacular form of stellar obituary. Since B2FH, the physical processes underlying their eruptive deaths have been known to play a key role in populating the ISM with metals beyond the iron peak. More recently, these celestial explosions have acquired even greater significance through the use of Type Ia supernovae as distance indicators in mapping the `dark energy' acceleration term of cosmic expansion. However, while there are well-established models for the two main types of supernovae (runaway fusion on the surface of a white dwarf in a binary system for Type Ia, or detonation of the core in Type II), some significant uncertainties remain concerning the physical details of the disruption, and, potentially, the overall uniformity of these events. Consequently, there is potential for systematic bias in the distance estimates. The present program aims to address this issue through detailed observations of a small number of relatively nearby Type Ia Sne, using the Space telescope Imagign Spectrograph to provide spectral coverage over the full UV and visual wavelength ergime. The program aims to pick up the supernovae before maximum, and take spectra at regular (~4 day) intervals, providing detailed coverage of the changing abundances within the SNe ejecta. This is a target of opportunity, and the present set of observations are aimed at SN 2015f in NGC 2442/2443, an active spiral galaxy, also known as the "Meathook", lying at a distance of ~20 Mpc. The supernova was discovered at 13th magnitude in mid-March. The first HST observations were made on March 16th, with subsequent observations through April 12th. |
GO 13856: Resolving the faint end of the satellite luminosity function for the nearest elliptical Cen A
A CTIO image of the active galaxy Centaurus A |
Lying at a distance of 3.7 Mpc, Centaurus A is both the nearest elliptical galaxy and the nearest active galaxy to the Milky Way. Originally catalogued in 1826 by James Dunlop, the system (as the name suggests) was one of the first radio sources detected in the southern sky. Detailed optical imaging over the past 50 years have highlighted the presence of a substantial dust lane with embedded star formation. This strongly suggests that the system is a early-type elliptical or lenticular galaxy that has recently ingested asmoderately massive, gas-rich spiral companion. X-ray and radio observations have revealed extensive jet-like structures almost perpendicular to the disk, indicating the presence of a central black hole. The present observations, however, are focused not on Cen A itself, but on its immediate environs. Ground-based observations with the Magellan telescope have identified up to 15 candidate low-mass dwarf satellite companions. The present observations aim to use the Advanced Camera for Surveys on HST to investigate these candidates in more detail, and probe their likely mass and star formation history. |
GO 14193: Footprints of the Magnetosphere: the Star-Disk Connection in T Tauri Stars
An artist's representation of magnetic interactions between a T Tauri star and the surrounding disk |
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 significant accretion of material onto the central star, controlled to some extent by the stellar magnetic field. This leads to heating of the inner regions of the accretion disk, and significant emission at ultraviolet and X-ray wavelengths. Spitzer observations probe the structure of the cool dust disk at larger separations, but little is known regarding the properties of gas and dust in the innermost regions. The present program aims to probe those regions through coordinated multi-wavelength monitoring of two T Tauri stars in the Chamaeleon stellar association, VW Cha and T 56. Simultaneous observations will be obtained by Spitzer in the mid-infrared, Swift at UV and X-ray wavelengths, and with the Space Telescope Imaging Spectrograph on Hubble, covering UV and optical wavelengths. The goal is to use the emasured variability to constrain the conditions in the innermost 0.5 AU of the circumstellar disk. |
GO 14227: The CANDELS Lyman-alpha Emission At Reionization (CLEAR) Experiment
Part of the GOODS/Chandra Deep Field South field, as imaged by HST |
Hubble has made significant contributions in many science areas, but galaxy formation, assembly and evolution is a topic that has been transformed by the series of deep fields obtained over the past 20 years. CANDELS, one of three Multi-Cycle Treasury Program executed in cycles 18 through 20, is one of the more recent additions to this genre.Building on past investment of both space- and ground-based observational resources, it covers five five fields including both 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. CANDELS added new optical and near-infrared observations with WFC3 and ACS (see this link for more details). Those data have been processed and analysed by both the CANDELS team and by other groups within the community. The present program builds on this foundation by adding 16 pointings within the CANDELS fields with the WFC3 G102 grism. The goal is to probe reionisation by measuring the strength of Lyman-alpha absorption in galaxies at redshifts between z=6.5 and z=8.2. The expectation is that the ovall absorption strength should decrease with decreasing redshift as the intergalactic medium is ionised, and the proportion of neutral gas decreases. |