Search Publications
A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies. I. Galaxy Mergers and Quasar Activity
Hernquist, Lars; Cox, Thomas J.; Hopkins, Philip F. +1 more
We develop a model for the cosmological role of mergers in the evolution of starbursts, quasars, and spheroidal galaxies. By combining theoretically well-constrained halo and subhalo mass functions as a function of redshift and environment with empirical halo occupation models, we can estimate where galaxies of given properties live at a particula…
The Chandra Deep Field-South Survey: 2 Ms Source Catalogs
Smail, I.; Finoguenov, A.; Lehmer, B. D. +19 more
We present point-source catalogs for the ≈2 Ms exposure of the Chandra Deep Field-South (CDF-S); this is one of the two most sensitive X-ray surveys ever performed. The survey covers an area of ≈436 arcmin2 and reaches on-axis sensitivity limits of ≈1.9 × 10-17 and ≈1.3 × 10-16 ergs cm-2 s-1 f…
A High-Resolution Survey of Low-Redshift QSO Absorption Lines: Statistics and Physical Conditions of O VI Absorbers
Richter, Philipp; Bowen, David V.; Tripp, Todd M. +4 more
Using high-resolution ultraviolet spectra of 16 low-z QSOs obtained with the E140M echelle mode of the Space Telescope Imaging Spectrograph, we study the physical conditions and statistics of O VI absorption in the intergalactic medium (IGM) at z < 0.5. We identify 51 intervening (zabsll zQSO) O VI systems comprising 77 in…
A New Method to Separate Star-forming from AGN Galaxies at Intermediate Redshift: The Submillijansky Radio Population in the VLA-COSMOS Survey
Bondi, M.; Aussel, H.; Sanders, D. B. +21 more
We explore the properties of the submillijansky radio population at 20 cm by applying a newly developed optical color-based method to separate star-forming (SF) from active galactic nucleus (AGN) galaxies at intermediate redshifts (zlesssim 1.3). Although optical rest-frame colors are used, our separation method is shown to be efficient and not bi…
First Catalog of Strong Lens Candidates in the COSMOS Field
Refregier, Alexandre; Ellis, Richard; Schinnerer, Eva +19 more
We present the first catalog of 67 strong galaxy-galaxy lens candidates discovered in the 1.64 deg2 Hubble Space Telescope COSMOS survey. Twenty of these systems display multiple images or strongly curved large arcs. Our initial search is performed by visual inspection of the data and is restricted, for practical considerations, to mass…
The Far Ultraviolet Spectroscopic Explorer Survey of O VI Absorption in the Disk of the Milky Way
Bowen, David V.; Tripp, Todd M.; Jenkins, Edward B. +12 more
To probe the distribution and physical characteristics of interstellar gas at temperatures T ≈ 3 × 105 K in the disk of the Milky Way, we have used the Far Ultraviolet Spectroscopic Explorer (FUSE) to observe absorption lines of O VI λ1032 toward 148 early-type stars situated at distances >1 kpc. After subtracting off a mild excess o…
Spitzer IRS Spectra and Envelope Models of Class I Protostars in Taurus
Watson, D. M.; Furlan, E.; Sargent, B. +8 more
We present Spitzer Infrared Spectrograph (IRS) spectra of 28 Class I protostars in the Taurus star-forming region. The 5-36 µm spectra reveal excess emission from the inner regions of the envelope and accretion disk surrounding these predecessors of low-mass stars, as well as absorption features due to silicates and ices. Together with short…
Circumnuclear Gas in Seyfert 1 Galaxies: Morphology, Kinematics, and Direct Measurement of Black Hole Masses
Malkan, Matthew A.; Hicks, Erin K. S.
The two-dimensional (2D) distribution and kinematics of the molecular, ionized, and highly ionized gas in the nuclear regions of Seyfert 1 galaxies have been measured using high spatial resolution (~0.09'') near-infrared spectroscopy from NIRSPEC with adaptive optics on the Keck telescope. Molecular hydrogen, H2, is detected in all nine…
The VLA Survey of the Chandra Deep Field-South. I. Overview and the Radio Data
Tozzi, P.; Mainieri, V.; Rosati, P. +5 more
We report 20 and 6 cm VLA deep observations of the CDF-S including the Extended CDF-S. We discuss the radio properties of 266 cataloged radio sources, of which 198 are above a 20 cm completeness level reaching down to 43 µJy at the center of the field. Survey observations made at 6 cm over a more limited region cover the original CDF-S to a …
The Hubble Space Telescope Advanced Camera for Surveys Coma Cluster Survey. I. Survey Objectives and Design
Ferguson, Henry C.; Mobasher, Bahram; Miller, Bryan W. +34 more
We describe the HST ACS Coma Cluster Treasury survey, a deep two-passband imaging survey of one of the nearest rich clusters of galaxies, the Coma Cluster (Abell 1656). The survey was designed to cover an area of 740 arcmin2 in regions of different density of both galaxies and intergalactic medium within the cluster. The ACS failure of …