Related papers: Dynamical analysis of strong-lensing galaxy groups…
We present the first results of a MOS campaign to follow up cluster candidates located via weak lensing. Our main goals are to search for spatial concentrations of galaxies that are plausible optical counterparts of the weak lensing…
The gravitational lens system CLASS B2108+213 has two radio-loud lensed images separated by 4.56 arcsec. The relatively large image separation implies that the lensing is caused by a group of galaxies. In this paper, new optical imaging and…
We analyse the stellar and hot gas content of 18 nearby, low-mass galaxy clusters, detected in redshift space and selected to have a dynamical mass 3E14<M/Msun<6E14, as measured from the 2dF Galaxy Redshift Survey. We combine X-ray…
We present the first automated spectroscopic search for disk-galaxy lenses, using the Sloan Digital Sky Survey database. We follow up eight gravitational lens candidates, selected among a sample of ~40000 candidate massive disk galaxies,…
Bright gravitationally lensed galaxies provide our most detailed view of galaxies at high redshift. Yet as a result of the small number of ultra-bright z~2 lensed systems with confirmed redshifts, most detailed spectroscopic studies have…
Galaxies located in the environment or on the line of sight towards gravitational lenses can significantly affect lensing observables, and can lead to systematic errors on the measurement of $H_0$ from the time-delay technique. We present…
We present the first weak gravitational lensing analysis of the completed Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). We study the 64 square degrees W1 field, the largest of the CFHTLS-Wide survey fields, and present the largest…
Strong gravitational lensing and stellar dynamics provide two complementary and orthogonal constraints on the density profiles of galaxies. Based on spherically symmetric, scale-free, mass models, it is shown that the combination of both…
We calculate the expected lensing statistics of the galaxy population in large, low-redshift surveys. Galaxies are modeled using realistic, multiple components: a dark matter halo, a bulge component and disc. We use semi-analytic models of…
We report on the results of a spectroscopic survey of the environments of the gravitational lens systems CLASS B1600+434 (z_l = 0.41, z_s = 1.59) and CLASS B2319+051 (z_l = 0.62). The B1600+434 system has a time delay measured for it, and…
Strong gravitational lensing provides unique opportunities to investigate the mass distribution at the cores of galaxy clusters and to study high redshift galaxies. Using $94$ strong lensing models of $74$ cluster fields from the…
We present a joint gravitational lensing and stellar-dynamical analysis of 11 early-type galaxies (median deflector redshift $\zd=0.5$) from Strong Lenses in the Legacy Survey (SL2S). Using newly measured redshifts and stellar velocity…
A ``friends-of-friends'' percolation algorithm has been used to extract a catalogue of dn/n = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalogue contains 1495 groups and…
This is the third of a series of papers of low X-ray luminosity galaxy clusters. In this work we present the weak lensing analysis of eight clusters, based on observations obtained with the Gemini Multi-Object Spectrograph in the $g'$, $r'$…
Strong gravitational lensing observations can provide extremely valuable information on the structure of galaxies, but their interpretation is made difficult by selection effects, which, if not accounted for, introduce a bias between the…
A galaxy group catalog is built from the sample of the 2MASS Redshift Survey almost complete to Ks=11.75 over 91% of the sky. Constraints in the construction of the groups were provided by scaling relations determined by close examination…
According to the standard cosmological scenario, superclusters are objects that have just passed the turn around point and are collapsing. The dynamics of very few superclusters have been analysed up to now. In this paper we study the…
We present VLT/X-shooter spectra of 13 galaxies in the redshift range 1< z < 6, which are strongly lensed by massive galaxy clusters. Spectroscopic redshifts are measured for nine galaxies, while three sources have redshifts determined from…
We present the first result of a survey for strong galaxy-galaxy lenses in Sloan Digital Sky Survey (SDSS) images. SDSS J082728.70+223256.4 was selected as a lensing candidate using selection criteria based on the color and positions of…
In this work we analyze a sample of close galaxy pairs (relative projected separation $<25 h^{-1}$kpc and relative radial velocities $< 350$ km s$^{-1}$) using a weak lensing analysis based on the CFHT Stripe 82 Survey. We determine halo…