Search Publications
Blind Detections of CO J = 1-0 in 11 H-ATLAS Galaxies at z = 2.1-3.5 with the GBT/Zpectrometer
Ivison, R. J.; Frayer, D. T.; Clements, D. L. +29 more
We report measurements of the carbon monoxide ground state rotational transition (12C16O J = 1-0) with the Zpectrometer ultrawideband spectrometer on the 100 m diameter Green Bank Telescope. The sample comprises 11 galaxies with redshifts between z = 2.1 and 3.5 from a total sample of 24 targets identified by Herschel-ATLAS p…
The Primeval Populations of the Ultra-faint Dwarf Galaxies
Ferguson, Henry C.; Brown, Thomas M.; Geha, Marla +9 more
We present new constraints on the star formation histories of the ultra-faint dwarf (UFD) galaxies, using deep photometry obtained with the Hubble Space Telescope (HST). A galaxy class recently discovered in the Sloan Digital Sky Survey, the UFDs appear to be an extension of the classical dwarf spheroidals to low luminosities, offering a new front…
A Swift Look at SN 2011fe: The Earliest Ultraviolet Observations of a Type Ia Supernova
Gronwall, Caryl; Milne, Peter; Kuin, Paul +8 more
We present the earliest ultraviolet (UV) observations of the bright Type Ia supernova SN 2011fe/PTF11kly in the nearby galaxy M101 at a distance of only 6.4 Mpc. It was discovered shortly after explosion by the Palomar Transient Factory and first observed by Swift/UVOT about a day after explosion. The early UV light is well defined, with ~20 data …
Sigmoidal Active Region on the Sun: Comparison of a Magnetohydrodynamical Simulation and a Nonlinear Force-free Field Model
Aulanier, G.; Pariat, E.; Savcheva, A. +2 more
In this paper we show that when accurate nonlinear force-free field (NLFFF) models are analyzed together with high-resolution magnetohydrodynamic (MHD) simulations, we can determine the physical causes for the coronal mass ejection (CME) eruption on 2007 February 12. We compare the geometrical and topological properties of the three-dimensional ma…
Modeling Dust and Starlight in Galaxies Observed by Spitzer and Herschel: NGC 628 and NGC 6946
Helou, G.; Roussel, H.; Murphy, E. J. +26 more
We characterize the dust in NGC 628 and NGC 6946, two nearby spiral galaxies in the KINGFISH sample. With data from 3.6 µm to 500 µm, dust models are strongly constrained. Using the Draine & Li dust model (amorphous silicate and carbonaceous grains), for each pixel in each galaxy we estimate (1) dust mass surface density, (2) dust …
Star Formation in the Early Universe: Beyond the Tip of the Iceberg
Greiner, J.; Kouveliotou, C.; Fruchter, A. S. +18 more
We present late-time Hubble Space Telescope (HST) imaging of the fields of six Swift gamma-ray bursts (GRBs) lying at 5.0 <~ z <~ 9.5. Our data include very deep observations of the field of the most distant spectroscopically confirmed burst, GRB 090423, at z = 8.2. Using the precise positions afforded by their afterglows, we can place strin…
The M31 Velocity Vector. I. Hubble Space Telescope Proper-motion Measurements
Anderson, Jay; van der Marel, Roeland P.; Sohn, Sangmo Tony
We present the first proper-motion (PM) measurements for the galaxy M31. We obtained new V-band imaging data with the Hubble Space Telescope ACS/WFC and the WFC3/UVIS instruments of three fields: a spheroid field near the minor axis, an outer disk field along the major axis, and a field on the Giant Southern Stream. The data provide five to seven …
Deep Absorption Line Studies of Quiescent Galaxies at z ~ 2: The Dynamical-mass-Size Relation and First Constraints on the Fundamental Plane
Grillo, C.; Toft, S.; Zibetti, S. +4 more
We present dynamical and structural scaling relations of quiescent galaxies at z = 2, including the dynamical-mass-size relation and the first constraints on the fundamental plane (FP). The backbone of the analysis is a new, very deep Very Large Telescope/X-shooter spectrum of a massive, compact, quiescent galaxy at z = 2.0389. We detect the conti…
High-velocity Outflows without AGN Feedback: Eddington-limited Star Formation in Compact Massive Galaxies
Moustakas, John; Coil, Alison L.; Rudnick, Gregory H. +5 more
We present the discovery of compact, obscured star formation in galaxies at z ~ 0.6 that exhibit >~ 1000 km s-1 outflows. Using optical morphologies from the Hubble Space Telescope and infrared photometry from the Wide-field Infrared Survey Explorer, we estimate star formation rate (SFR) surface densities that approach ΣSFR
Dynamical Measurements of Black Hole Masses in Four Brightest Cluster Galaxies at 100 Mpc
Ma, Chung-Pei; Graham, James R.; Gebhardt, Karl +5 more
We present stellar kinematics and orbit superposition models for the central regions of four brightest cluster galaxies, based upon integral-field spectroscopy at Gemini, Keck, and McDonald Observatories. Our integral-field data span radii from <100 pc to tens of kiloparsecs, comparable to the effective radius of each galaxy. We report black ho…