Search Publications
A Direct Empirical Proof of the Existence of Dark Matter
Bradač, Maruša; Jones, Christine; Gonzalez, Anthony H. +4 more
We present new weak-lensing observations of 1E 0657-558 (z=0.296), a unique cluster merger, that enable a direct detection of dark matter, independent of assumptions regarding the nature of the gravitational force law. Due to the collision of two clusters, the dissipationless stellar component and the fluid-like X-ray-emitting plasma are spatially…
Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships
Peterson, Bradley M.; Vestergaard, Marianne
We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy. These mass scaling relationships between line widths and luminosity are based on recently improved empirical relationships between the broad-line …
The Sloan Lens ACS Survey. III. The Structure and Formation of Early-Type Galaxies and Their Evolution since z ~ 1
Treu, Tommaso; Koopmans, Léon V. E.; Bolton, Adam S. +2 more
We present a joint gravitational lensing and stellar-dynamical analysis of 15 massive field early-type galaxies selected from the Sloan Lens ACS (SLACS) Survey. The following numerical results are found: (1) A joint likelihood gives an average logarithmic density slope for the total mass density of <γ'>=2.01+0.02-0…
High-Resolution Millimeter Imaging of Submillimeter Galaxies
Smail, I.; Genzel, R.; Tacconi, L. J. +8 more
We present ~0.6" resolution IRAM PdBI interferometry of eight submillimeter galaxies at z~2-3.4, where we detect continuum at 1 mm and/or CO lines at 3 and 1 mm. The CO 3-2/4-3 line profiles in five of the sources are double-peaked, indicative of orbital motion either in a single rotating disk or of a merger of two galaxies. The millimeter line an…
The Size Evolution of Galaxies since z~3: Combining SDSS, GEMS, and FIRES
van Dokkum, Pieter G.; Franx, Marijn; Labbé, Ivo +15 more
We present the evolution of the luminosity-size and stellar mass-size relations of luminous (LV>~3.4×1010 h-270 Lsolar) and massive (M*>~3×1010 h-270 Msolar) galaxies in the last ~11 Gyr. We use very deep near-infrared images of the …
The Sloan Lens ACS Survey. I. A Large Spectroscopically Selected Sample of Massive Early-Type Lens Galaxies
Treu, Tommaso; Koopmans, Léon V. E.; Bolton, Adam S. +2 more
The Sloan Lens ACS (SLACS) Survey is an efficient Hubble Space Telescope (HST) Snapshot imaging survey for new galaxy-scale strong gravitational lenses. The targeted lens candidates are selected spectroscopically from the Sloan Digital Sky Survey (SDSS) database of galaxy spectra for having multiple nebular emission lines at a redshift significant…
Damped Lyα Systems at z<1.65: The Expanded Sloan Digital Sky Survey Hubble Space Telescope Sample
Turnshek, David A.; Rao, Sandhya M.; Nestor, Daniel B.
We present results of our Hubble Space Telescope Cycle 11 survey for low-redshift (z<1.65) damped Lyα (DLA) systems in the UV spectra of quasars selected from the Sloan Digital Sky Survey (SDSS) Early Data Release. These quasars have strong intervening Mg II-Fe II systems that are known signatures of high column density neutral gas. In total, i…
The ACS Virgo Cluster Survey. IX. The Color Distributions of Globular Cluster Systems in Early-Type Galaxies
Jordán, Andrés; Tonry, John L.; Côté, Patrick +7 more
We present the color distributions of globular cluster (GC) systems for 100 early-type galaxies observed in the ACS Virgo Cluster Survey, the deepest and most homogeneous survey of this kind to date. On average, galaxies at all luminosities in our study (-22<MB<-15) appear to have bimodal or asymmetric GC color distributions. Almo…
Probing the Coevolution of Supermassive Black Holes and Galaxies Using Gravitationally Lensed Quasar Hosts
Rix, Hans-Walter; Keeton, Charles R.; Kochanek, Christopher S. +5 more
In the present-day universe, supermassive black hole masses (MBH) appear to be strongly correlated with their galaxy's bulge luminosity, among other properties. In this study we explore the analogous relationship between MBH, derived using the virial method, and the stellar R-band bulge luminosity (LR) or stellar b…
The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements
Peterson, Bradley M.; Pogge, Richard W.; Vestergaard, Marianne +2 more
We have obtained high-resolution images of the central regions of 14 reverberation-mapped active galactic nuclei (AGNs) using the Hubble Space Telescope Advanced Camera for Surveys High Resolution Camera to account for host-galaxy starlight contamination of measured AGN luminosities. We measure the host-galaxy starlight contribution to the continu…