Search Publications
Unmasking the Supernova Impostors
Kochanek, C. S.; Stanek, K. Z.; Szczygieł, D. M.
The canonical picture of a supernova impostor is a short (~months) -11 <~ MV <~ -14 optical transient from a massive (M * >~ 40 M ⊙) star during which the star ejects a dense shell of material. Dust formed in the ejecta then obscures the star. In this picture, the geometric expansion of the shell leads to …
The Optically Unbiased GRB Host (TOUGH) Survey. V. VLT/X-shooter Emission-line Redshifts for Swift GRBs at z ~ 2
Hjorth, Jens; Fynbo, Johan P. U.; Milvang-Jensen, Bo +7 more
We present simultaneous optical and near-infrared (NIR) spectroscopy of 19 Swift γ-ray burst (GRB) host galaxies observed with the VLT/X-shooter with the aim of measuring their redshifts. Galaxies were selected from The Optically Unbiased GRB Host (TOUGH) survey (15 of the 19 galaxies) or because they hosted GRBs without a bright optical afterglow…
Spectral Energy Distributions of Type 1 Active Galactic Nuclei in the COSMOS Survey. I. The XMM-COSMOS Sample
Liu, Y.; Aussel, H.; Le Floc'h, E. +39 more
The "Cosmic Evolution Survey" (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM > 2000 km s-1) AGNs with …
Weak Lensing Measurement of Galaxy Clusters in the CFHTLS-Wide Survey
Massey, Richard; Kneib, Jean-Paul; Rhodes, Jason +7 more
We present the first weak gravitational lensing analysis of the completed Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). We study the 64 deg2 W1 field, the largest of the CFHTLS-Wide survey fields, and present the largest contiguous weak lensing convergence "mass map" yet made. 2.66 million galaxy shapes are measured, using the …
The Slow Death (Or Rebirth?) of Extended Star Formation in z ~ 0.1 Green Valley Early-type Galaxies
Faber, S. M.; Salim, Samir; Rich, R. Michael +2 more
UV observations in the local universe have uncovered a population of early-type galaxies with UV flux consistent with low-level recent or ongoing star formation. Understanding the origin of such star formation remains an open issue. We present resolved UV-optical photometry of a sample of 19 Sloan Digital Sky Survey (SDSS) early-type galaxies at z…
The Assembly of the Red Sequence at z ~ 1: The Color and Spectral Properties of Galaxies in the Cl1604 Supercluster
Surace, J. A.; Fassnacht, C. D.; Kocevski, D. D. +6 more
We investigate the properties of the 525 spectroscopically confirmed members of the Cl1604 supercluster at z ~ 0.9 as part of the Observations of Redshift Evolution in Large Scale Environments survey. In particular, we focus on the photometric, stellar mass, morphological, and spectral properties of the 305 member galaxies of the eight clusters an…
On the Role of Rotating Sunspots in the Activity of Solar Active Region NOAA 11158
Maurya, R. A.; Ambastha, A.; Vemareddy, P.
We study the role of rotating sunspots in relation to the evolution of various physical parameters characterizing the non-potentiality of the active region (AR) NOAA 11158 and its eruptive events using the magnetic field data from the Helioseismic and Magnetic Imager (HMI) and multi-wavelength observations from the Atmospheric Imaging Assembly (AI…
The Near-infrared Background Intensity and Anisotropies during the Epoch of Reionization
Gong, Yan; Cooray, Asantha; Smidt, Joseph +1 more
A fraction of the extragalactic near-infrared (near-IR) background light involves redshifted photons from the ultraviolet (UV) emission from galaxies present during reionization at redshifts above 6. The absolute intensity and the anisotropies of the near-IR background provide an observational probe of the first-light galaxies and their spatial di…
A 10 kpc Scale Seyfert Galaxy Outflow: HST/COS Observations of IRAS F22456-5125
Kriss, Gerard A.; Arav, Nahum; Edmonds, Doug +2 more
We present analysis of the UV spectrum of the low-z AGN IRAS F22456-5125 obtained with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The spectrum reveals six main kinematic components, spanning a range of velocities of up to 800 km s-1, which for the first time are observed in troughs associated with C II, C IV, N…
A Non-radial Eruption in a Quadrupolar Magnetic Configuration with a Coronal Null
Liu, Yang; Hayashi, Keiji; Sun, Xudong +2 more
We report one of the several homologous non-radial eruptions from NOAA active region (AR) 11158 that are strongly modulated by the local magnetic field as observed with the Solar Dynamic Observatory. A small bipole emerged in the sunspot complex and subsequently created a quadrupolar flux system. Nonlinear force-free field extrapolation from vecto…