Search Publications
The Evolution of Galaxy Size and Morphology at z ~ 0.5-3.0 in the GOODS-N Region with Hubble Space Telescope/WFC3 Data
Kajisawa, Masaru; Morishita, Takahiro; Ichikawa, Takashi
We analyze the recently released Hubble Space Telescope/Wide Field Camera 3 IR images in the GOODS-N region to study the formation and evolution of quiescent galaxies (QGs). After examining the reliability of two-dimensional light profiles with artificial galaxies, we obtain the morphological parameters with Sérsic profile of 299 QGs and 1083 star…
WISE Y Dwarfs as Probes of the Brown Dwarf-Exoplanet Connection
Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R. +5 more
We have determined astrometric positions for 15 WISE-discovered late-type brown dwarfs (six T8-9 and nine Y dwarfs) using the Keck-II telescope, the Spitzer Space Telescope, and the Hubble Space Telescope. Combining data from 8 to 20 epochs we derive parallactic and proper motions for these objects, which puts the majority within 15 pc. For ages g…
Winds of Low-metallicity OB-type Stars: HST-COS Spectroscopy in IC 1613
Garcia, Miriam; Herrero, Artemio; Najarro, Francisco +2 more
We present the first quantitative ultraviolet spectroscopic analysis of resolved OB stars in IC 1613. Because of its alleged very low metallicity (lsim1/10 Z ⊙, from H II regions), studies in this Local Group dwarf galaxy could become a significant step forward from the Small Magellanic Cloud (SMC) toward the extremely metal-poor massiv…
Revealing Asymmetries in the HD 181327 Debris Disk: A Recent Massive Collision or Interstellar Medium Warping
Stark, Christopher C.; Weinberger, Alycia J.; Debes, John H. +4 more
New multi-roll coronagraphic images of the HD 181327 debris disk obtained using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope reveal the debris ring in its entirety at high signal-to-noise ratio and unprecedented spatial resolution. We present and apply a new multi-roll image processing routine to identify and furthe…
CARMA Large Area Star Formation Survey: Structure and Kinematics of Dense Gas in Serpens Main
Kwon, Woojin; Rosolowsky, Erik; Kauffmann, Jens +21 more
We present observations of N2H+ (J = 1 → 0), HCO+ (J = 1 → 0), and HCN (J = 1 → 0) toward the Serpens Main molecular cloud from the CARMA Large Area Star Formation Survey (CLASSy). We mapped 150 arcmin2 of Serpens Main with an angular resolution of ~7''. The gas emission is concentrated in two subcluster…
Five Debris Disks Newly Revealed in Scattered Light from the Hubble Space Telescope NICMOS Archive
Schneider, Glenn; Hines, Dean C.; Perrin, Marshall D. +12 more
We have spatially resolved five debris disks (HD 30447, HD 35841, HD 141943, HD 191089, and HD 202917) for the first time in near-infrared scattered light by reanalyzing archival Hubble Space Telescope (HST)/NICMOS coronagraphic images obtained between 1999 and 2006. One of these disks (HD 202917) was previously resolved at visible wavelengths usi…
Cold and Warm Atomic Gas around the Perseus Molecular Cloud. I. Basic Properties
Murray, Claire E.; Stanimirović, Snežana; Lee, Min-Young +2 more
Using the Arecibo Observatory, we have obtained neutral hydrogen (HI) absorption and emission spectral pairs in the direction of 26 background radio continuum sources in the vicinity of the Perseus molecular cloud. Strong absorption lines were detected in all cases, allowing us to estimate spin temperature (Ts ) and optical depth for 10…
The Supernova Progenitor Mass Distributions of M31 and M33: Further Evidence for an Upper Mass Limit
Dolphin, Andrew E.; Williams, Benjamin F.; Gilbert, Karoline M. +5 more
Using Hubble Space Telescope photometry to measure star formation histories, we age-date the stellar populations surrounding supernova remnants (SNRs) in M31 and M33. We then apply stellar evolution models to the ages to infer the corresponding masses for their supernova progenitor stars. We analyze 33 M33 SNR progenitors and 29 M31 SNR progenitor…
An Accreting White Dwarf near the Chandrasekhar Limit in the Andromeda Galaxy
Cenko, S. Bradley; Kong, Albert K. H.; Perley, Daniel A. +13 more
The intermediate Palomar Transient Factory (iPTF) detection of the most recent outburst of the recurrent nova (RN) system RX J0045.4+4154 in the Andromeda galaxy has enabled the unprecedented study of a massive (M > 1.3 M ⊙) accreting white dwarf (WD). We detected this nova as part of the near-daily iPTF monitoring of M31 to a depth …
The Host Galaxies of Fast-ejecta Core-collapse Supernovae
Filippenko, Alexei V.; Kelly, Patrick L.; Modjaz, Maryam +1 more
Spectra of broad-lined Type Ic supernovae (SNe Ic-BL), the only kind of SN observed at the locations of long-duration gamma-ray bursts (LGRBs), exhibit wide features indicative of high ejecta velocities (~0.1c). We study the host galaxies of a sample of 245 low-redshift (z < 0.2) core-collapse SNe, including 17 SNe Ic-BL, discovered by galaxy-u…