Related papers: Mass Substructure in Abell 3128

Cosmological constraints from galaxy clusters rely on accurate measurements of the mass and internal structure of clusters. An important source of systematic uncertainty in cluster mass and structure measurements is the secure selection of…

A weak-lensing analysis of wide-field $V$- and $I$-band images centered on the cluster Abell 1942 has uncovered a mass concentration $\sim 7$ arcminutes South of the cluster center. A statistical analysis shows that the detections are…

We report the discovery of a binary galaxy cluster merger via a search of the redMaPPer optical cluster catalog, with a projected separation of 535 kpc between the BCGs. Archival XMM-Newton spectro-imaging reveals a gas peak between the…

We present the first galaxy evolution results from the Local Cluster Substructure Survey (LoCuSS), a multi-wavelength survey of 100 X-ray selected galaxy clusters at 0.15<z<0.30. LoCuSS combines far-UV through far-IR observations of cluster…

Utilizing the James Webb Space Telescope Early Release NIRCam Observations, we perform a weak-lensing analysis of the massive galaxy cluster SMACS J0723.3-7327 ($z=0.39$). We investigate the spatial variation of the PSF from the stars in…

We examine the inner mass distribution of the relaxed galaxy cluster Abell 383 in deep 16-band HST/ACS+WFC3 imaging taken as part of the CLASH multi-cycle treasury program. Our program is designed to study the dark matter distribution in 25…

Mapping the small-scale structure of the universe through gravitational lensing is a promising tool for probing the particle nature of dark matter. Curved Arc Basis (CAB) has been proposed as a local lensing formalism in galaxy clusters,…

We present a study of the dynamical properties of 125 compact stellar systems (CSSs) in the nearby giant elliptical galaxy NGC5128, using high-resolution spectra (R 26,000) obtained with VLT/FLAMES. Our results provide evidence for a new…

We describe a new non-parametric technique for reconstructing the mass distribution in galaxy clusters with strong lensing, i.e., from multiple images of background galaxies. The observed positions and redshifts of the images are considered…

Gravitational lensing magnifies the luminosity of galaxies behind the lens. We use this effect to constrain the total mass in the cluster Abell 1689 by comparing the lensed luminosities of background galaxies with the luminosity function of…

Complementary one-, two-, and three-dimensional tests for detecting the presence of substructure in clusters of galaxies are applied to recently obtained data from the 2dF Galaxy Redshift Survey. The sample of 25 clusters used in this study…

A mass model of the rich cluster A2218 is presented based on optical and new near-infrared images of arc(let)s and the ROSAT/HRI X-ray map. A lensing model is proposed with two dark matter clumps, centered on the two bright galaxies around…

We present weak lensing data from the HST/STAGES survey to study the three-dimensional spatial distribution of matter and galaxies in the Abell 901/902 supercluster complex. Our method improves over the existing 3D lensing mapping…

Current efforts in observational cosmology are focused on characterizing the mass-energy content of the Universe. We present results from a geometric test based on strong lensing in galaxy clusters. Based on Hubble Space Telescope images…

The tidal gravitational field of galaxy clusters causes a coherent distortion of the images of background sources. Since the distribution of image distortions, namely the shear field, traces the local gravitational potential of a deflector,…

Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These "mass maps" provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In…

The nature of the elusive dark matter can be probed by comparing the predictions of the cold dark matter framework with the gravitational field of massive galaxy clusters. However, a robust test of dark matter can only be achieved if the…

This is the first in a series of papers in which we measure accurate weak-lensing masses for 51 of the most X-ray luminous galaxy clusters known at redshifts 0.15<z<0.7, in order to calibrate X-ray and other mass proxies for cosmological…

We present evidence for the existence of significant substructure in the cold front cluster Abell 3667 based on multi-object spectroscopy taken with the 3.9m Anglo Australian Telescope. This paper is the second in a series analyzing the…

The Blanco DECam Bulge Survey (BDBS) imaged more than 200 square degrees of the Southern Galactic bulge using the ugrizY filters of the Dark Energy Camera, and produced point spread function photometry of approximately 250 million unique…