Search Publications
Spiral Arms in the Asymmetrically Illuminated Disk of MWC 758 and Constraints on Giant Planets
Kuzuhara, M.; Tamura, M.; Ishii, M. +71 more
We present the first near-IR scattered light detection of the transitional disk associated with the Herbig Ae star MWC 758 using data obtained as part of the Strategic Exploration of Exoplanets and Disks with Subaru, and 1.1 µm Hubble Space Telescope/NICMOS data. While submillimeter studies suggested there is a dust-depleted cavity with r = …
The Era of Star Formation in Galaxy Clusters
Chary, R. -R.; Stern, D.; Pope, A. +17 more
We analyze the star formation properties of 16 infrared-selected, spectroscopically confirmed galaxy clusters at 1 < z < 1.5 from the Spitzer/IRAC Shallow Cluster Survey (ISCS). We present new spectroscopic confirmation for six of these high-redshift clusters, five of which are at z > 1.35. Using infrared luminosities measured with deep S…
A Population of Massive, Luminous Galaxies Hosting Heavily Dust-obscured Gamma-Ray Bursts: Implications for the Use of GRBs as Tracers of Cosmic Star Formation
Cenko, S. B.; Bloom, J. S.; Filippenko, A. V. +13 more
We present observations and analysis of the host galaxies of 23 heavily dust-obscured gamma-ray bursts (GRBs) observed by the Swift satellite during the years 2005-2009, representing all GRBs with an unambiguous host-frame extinction of AV > 1 mag from this period. Deep observations with Keck, Gemini, Very Large Telescope, Hubble Spa…
Stellar Velocity Dispersion Measurements in High-luminosity Quasar Hosts and Implications for the AGN Black Hole Mass Scale
Ferrarese, L.; Martini, P.; Peterson, B. M. +7 more
We present new stellar velocity dispersion measurements for four luminous quasars with the Near-Infrared Integral Field Spectrometer instrument and the ALTAIR laser guide star adaptive optics system on the Gemini North 8 m telescope. Stellar velocity dispersion measurements and measurements of the supermassive black hole (BH) masses in luminous qu…
Gravitational Lens Models Based on Submillimeter Array Imaging of Herschel-selected Strongly Lensed Sub-millimeter Galaxies at z > 1.5
Maiolino, R.; Pérez-Fournon, I.; Ivison, R. J. +46 more
Strong gravitational lenses are now being routinely discovered in wide-field surveys at (sub-)millimeter wavelengths. We present Submillimeter Array (SMA) high-spatial resolution imaging and Gemini-South and Multiple Mirror Telescope optical spectroscopy of strong lens candidates discovered in the two widest extragalactic surveys conducted by the …
The Changing Lyα Optical Depth in the Range 6 < z < 9 from the MOSFIRE Spectroscopy of Y-dropouts
Stiavelli, Massimo; Schmidt, Kasper B.; Treu, Tommaso +2 more
We present the MOSFIRE spectroscopy of 13 candidate z ~ 8 galaxies selected as Y-dropouts as part of the Brightest of Reionization Galaxies pure parallel survey. We detect no significant Lyα emission (our median 1σ rest-frame equivalent width sensitivity is in the range 2-16 Å). Using the Bayesian framework derived in a previous paper, we perform …
An Intensely Star-forming Galaxy at z ~ 7 with Low Dust and Metal Content Revealed by Deep ALMA and HST Observations
Ono, Yoshiaki; Ouchi, Masami; Kurono, Yasutaka +10 more
We report deep ALMA observations complemented by associated Hubble Space Telescope (HST) imaging for a luminous (m UV = 25) galaxy, "Himiko," at a redshift of z = 6.595. The galaxy is remarkable for its high star formation rate, 100 M ⊙ yr-1, which has been securely estimated from our deep HST and Spitzer photometr…
A Young Protoplanet Candidate Embedded in the Circumstellar Disk of HD 100546
Amara, Adam; Meyer, Michael R.; Girard, Julien H. +3 more
We present high-contrast observations of the circumstellar environment of the Herbig Ae/Be star HD 100546. The final 3.8 µm image reveals an emission source at a projected separation of 0.''48 ± 0.''04 (corresponding to ~47 ± 4 AU) at a position angle of 8.°9 ± 0.°9. The emission appears slightly extended with a point source component with a…
Direct Evidence for a Fast Coronal Mass Ejection Driven by the Prior Formation and Subsequent Destabilization of a Magnetic Flux Rope
Patsourakos, S.; Stenborg, G.; Vourlidas, A.
Magnetic flux ropes play a central role in the physics of coronal mass ejections (CMEs). Although a flux-rope topology is inferred for the majority of coronagraphic observations of CMEs, a heated debate rages on whether the flux ropes pre-exist or whether they are formed on-the-fly during the eruption. Here, we present a detailed analysis of extre…
The Stellar Initial Mass Function of Ultra-faint Dwarf Galaxies: Evidence for IMF Variations with Galactic Environment
Ferguson, Henry C.; Brown, Thomas M.; Geha, Marla +8 more
We present constraints on the stellar initial mass function (IMF) in two ultra-faint dwarf (UFD) galaxies, Hercules and Leo IV, based on deep Hubble Space Telescope Advanced Camera for Surveys imaging. The Hercules and Leo IV galaxies are extremely low luminosity (MV = -6.2, -5.5), metal-poor (lang[Fe/H]rang = -2.4, -2.5) systems that h…