Related papers: Comparison of Cluster Lensing Profiles with Lambda…
The concentration - virial mass relation is a well-defined trend that reflects the formation of structure in an expanding Universe. Numerical simulations reveal a marked correlation that depends on the collapse time of dark matter halos and…
Using stellar dynamics and strong gravitational lensing as complementary probes, Sand et al. (2002, 2003) have recently claimed strong evidence for shallow dark matter density profiles in several lensing clusters, which may conflict with…
Small distortions in the images of Einstein rings or giant arcs offer the exciting prospect of detecting dark matter haloes or subhaloes of mass below $10^9$M$_{\odot}$, most of which are too small to have made a visible galaxy. A very…
We present the results of an ongoing weak lensing survey conducted with the Subaru telescope whose initial goal is to locate and study the distribution of shear-selected structures or halos. Using a Suprime-cam imaging survey spanning 21.82…
Subaru observations of A1689 (z=0.183) are used to derive an accurate, model-independent mass profile for the entire cluster, r<2 Mpc/h, by combining magnification bias and distortion measurements. The projected mass profile steepens…
The presence of an invisible substructure has previously been detected in the gravitational lens galaxy SDSSJ0946+1006 through its perturbation of the lensed images. Using flexible models for the main halo and the subhalo perturbation to…
Lambda cold dark matter paradigm predicts that galaxy clusters follow an universal mass density profile and fit a well defined mass-concentration relation, with lensing clusters being preferentially triaxial haloes elongated along the line…
The alignment of clusters of galaxies with their nearest neighbours and between clusters within a supercluster is investigated using simulations of 512^{3} dark matter particles for \LambdaCDM and \tauCDM cosmological models. Strongly…
We present a comprehensive analysis of strong-lensing, weak-lensing shear and magnification data for a sample of 16 X-ray-regular and 4 high-magnification galaxy clusters selected from the CLASH survey. Our analysis combines constraints…
We examine gravitational lensing constraints on the structure of galaxy clusters and compare them with the results of cosmological N-body simulations of cluster formation in cold dark matter (CDM) dominated universes. We find that cluster…
Lensing flux-ratio anomalies have been frequently observed and taken as evidence for the presence of abundant dark matter substructures in lensing galaxies, as predicted by the cold dark matter (CDM) model of cosmogony. In previous work, we…
We study clusters in Warm Dark Matter (WDM) models of a thermally produced dark matter particle $0.5$ keV in mass. We show that, despite clusters in WDM cosmologies having similar density profiles as their Cold Dark Matter (CDM)…
Extensive surveys of galaxy clusters motivate us to assess the likelihood of cluster-cluster lensing (CCL), namely, gravitational-lensing of a background cluster by a foreground cluster. We briefly describe the characteristics of CCLs in…
Observation of even a single massive cluster, especially at high redshift, can falsify the standard cosmological framework consisting of a cosmological constant and cold dark matter (LCDM) with Gaussian initial conditions by exposing an…
A new, three-dimensional, shock capturing, TVD hydrodynamic code is utilized to determine the distribution of hot gas in a CDM$+\Lambda$ model universe. This open model succeeds in matching local observations of clusters in contrast to the…
Strong lensing is a powerful probe of the distribution of matter in the cores of clusters of galaxies. Recent studies suggest that the cold dark matter model predicts cores that are denser than those observed in galaxies, groups and…
This is the fifth in a series of papers studying the astrophysics and cosmology of massive, dynamically relaxed galaxy clusters. Our sample comprises 40 clusters identified as being dynamically relaxed and hot in Papers I and II of this…
Intrinsic variations of the projected density profiles of clusters of galaxies at fixed mass are a source of uncertainty for cluster weak lensing. We present a semi-analytical model to account for this effect, based on a combination of…
We study weak gravitational lensing of galaxy clusters in terms of the MOND (MOdified Newtonian Dynamics) theory. We calculate shears and convergences of background galaxies for three clusters (A1689, CL0024+1654, CL1358+6245) and the mean…
In the CDM scenario, dark matter halos are assembled hierarchically from smaller subunits. A long-standing problem with this picture is that the number of sub-halos predicted by CDM simulations is orders of magnitudes higher than the known…