Spectroscopic Redshifts for Seven Lens Galaxies

  title={Spectroscopic Redshifts for Seven Lens Galaxies},
  author={Eran. O. Ofek and Dan Maoz and Hans–Walter Rix and Christopher S. Kochanek and Emilio E. Falco},
  journal={The Astrophysical Journal},
  pages={70 - 77}
The use of gravitationally lensed quasars for cosmological applications and as probes of galaxy structure and evolution requires knowledge about the lens redshift, which is unknown for a large fraction of lenses. We report Very Large Telescope observations of 11 lensed quasars, designed to measure the redshifts of their lens galaxies. We successfully determined the redshifts for seven systems, five of which were previously unknown. The securely measured redshifts for the lensing galaxies are… 
Halo Structures of Gravitational Lens Galaxies
We explore the halo structure of four gravitational lenses with well-observed, thin Einstein rings. We find that the gravitational potentials are well described by ellipsoidal density distributions
COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses VI. Redshift of the lensing galaxy in seven gravitationally lensed quasars
Aims: The knowledge of the redshift of a lensing galaxy that produces multiple images of a background quasar is essential to any subsequent modeling, whether related to the determination of the
COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses. III. Redshift of the lensing galaxy
Aims. The knowledge of the redshift of a lensing galaxy that produces multiple images of a background quasar is essential to any subsequent modeling, whether related to the determination of the
With a large, unique spectroscopic survey in the fields of 28 galaxy-scale strong gravitational lenses, we identify groups of galaxies in the 26 adequately sampled fields. Using a group-finding
SDSS J120923.7+264047: a new massive galaxy cluster with a bright giant arc
Highly magnified lensed galaxies allow us to probe the morphological and spectroscopic properties of high-redshift stellar systems in great detail. However, such objects are rare, and there are only
SDSS J131339.98+515128.3: a new gravitationally lensed quasar selected based on near-infrared excess
We report the discovery of a new gravitationally lensed quasar, SDSS J131339.98+515128.3, at a redshift of 1.875 with an image separation of 1.24 arcsec. The lensing galaxy is clearly detected in
Prescriptions for Correcting Ultraviolet-based Redshifts for Luminous Quasars at High Redshift
High-redshift quasars typically have their redshift determined from rest-frame ultraviolet (UV) emission lines. However, these lines, and more specifically the prominent C iv λ1549 emission line, are
Doubly Imaged Quasar SDSS J1515+1511: Time Delay and Lensing Galaxies
We analyze new optical observations of the gravitational lens system SDSS J1515+1511. These include a 2.6-year photometric monitoring with the Liverpool Telescope (LT) in the r band, as well as a
Probing Structure in Cold Gas at z ≲ 1 with Gravitationally Lensed Quasar Sight Lines
Absorption spectroscopy of gravitationally lensed quasars (GLQs) enables study of spatial variations in the interstellar and/or circumgalactic medium of foreground galaxies. We report observations of
COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses VIII. Deconvolution of high resolution near-IR images and simple mass models for 7 gravitationally lensed quasars
Aims. We attempt to place very accurate positional constraints on seven gravitationally lensed quasars currently being monitored by the COSMOGRAIL collaboration, and shape parameters for the light


The Lens Redshift and Galaxy Environment for HE 0435−1223
The redshift of the galaxy lensing HE 0435-1223 is 0.4546 ± 0.0002, based on observations obtained with the Low Dispersion Survey Spectrograph 2 on the Magellan Consortium's 6.5 m Clay Telescope.
The Redshift of a Lensing Galaxy in PMN J0134–0931
The Sloan Digital Sky Survey (SDSS) automatically targeted as a quasar candidate the recently discovered, gravitationally lensed, extremely reddened z = 2.2 quasar PMN 0134-0931. The SDSS spectrum
Improved Cosmological Constraints from Gravitational Lens Statistics
We combine the Cosmic Lens All-Sky Survey (CLASS) with new Sloan Digital Sky Survey (SDSS) data on the local velocity dispersion distribution function of E/S0 galaxies, ϕ(σ), to derive lens
HE 0435-1223 : a wide separation quadruple QSO and gravitational lens
We report the discovery of a new gravitationally lensed QSO, at a redshift z = 1.689, with four QSO components in a cross-shaped arrangement around a bright galaxy. The maximum separation between
SDSS J092455.87+021924.9: An Interesting Gravitationally Lensed Quasar from the Sloan Digital Sky Survey
We report the discovery of a new gravitationally lensed quasar from the Sloan Digital Sky Survey, SDSS J092455.87+021924.9 (SDSS J0924+0219). This object was selected from among known SDSS quasars by
The Evolution and Structure of Early-Type Field Galaxies: A Combined Statistical Analysis of Gravitational Lenses
We introduce a framework for simultaneously investigating the structure and luminosity evolution of early-type gravitational lens galaxies. The method is based on the fundamental plane, which we
The Fundamental Plane of Gravitational Lens Galaxies and The Evolution of Early-Type Galaxies in Low-Density Environments
Most gravitational lenses are early-type galaxies in relatively low density environments—a "field" rather than a "cluster" population. Their average properties are the mass-averaged properties of all
HE 0047-1756: A new gravitationally lensed double QSO
The quasar HE 0047-1756, at $z=1.67$, is found to be split into two images $1\farcs44$ apart by an intervening galaxy acting as a gravitational lens. The flux ratio for the two components is roughly
The Cosmic Lens All‐Sky Survey: statistical strong lensing, cosmological parameters, and global properties of galaxy populations
Extensive analyses of statistical strong gravitational lensing are performed based on the final Cosmic Lens All-Sky Survey (CLASS) well-defined statistical sample of flat-spectrum radio sources and
Luminosity Evolution of Field Early-Type Galaxies to z = 0.55
We study the fundamental plane (FP) of field early-type galaxies at intermediate redshift, using Hubble Space Telescope Wide Field Planetary Camera 2 observations and deep Keck spectroscopy.