Weak lensing density profiles and mass reconstructions of the galaxy clusters Abell 1351 and Abell 1995

TL;DR

This study uses weak gravitational lensing to analyze the mass distribution of galaxy clusters Abell 1351 and Abell 1995, revealing their mass profiles, sub-structures, and comparing different modeling approaches.

Contribution

It provides detailed mass reconstructions and comparisons with spherical models for two galaxy clusters with contrasting structures, including detection of a sub-structure in Abell 1351.

Findings

Mass of Abell 1351: approximately 11.7 x 10^14 h_70^-1 Msun

Mass of Abell 1995: approximately 10.5 x 10^14 h_70^-1 Msun

Detection of a significant sub-structure in Abell 1351

Abstract

The aim of the present work is to study the overall mass distribution of the galaxy clusters Abell 1351 and Abell 1995 using weak gravitational lensing. These clusters have got a very different mass structure and dynamical state, and are the two extremes from a larger sample of 38 X-ray luminous clusters of similar size and redshift. We measure shear values of faint background galaxies and correct for PSF anisotropies using the KSB+ method. Two-dimensional mass maps of the clusters are created using a finite-field mass reconstruction algorithm, and verified with aperture mass statistics. The masses inferred from the reconstructions are compared to those obtained from fitting spherically symmetric SIS- and NFW-models to the tangential shear profiles. We discuss the NFW concentration parameters in detail. From the mass reconstructions we infer M200-masses of 11.7 +/- 3.1 * 10^14 h_70^-1 Msun and 10.5 +/- 2.7 * 10^14 h_70^-1 Msun for Abell 1351 and Abell 1995, respectively. About 3' north-east of the main mass peak of Abell 1351 we detect a significant secondary peak in the mass reconstruction as well as by aperture mass statistics. This feature is also traced by clusters members selected by means of their V-I colour, and hence is likely a real sub-structure of Abell 1351. From our fits to the tangential shear we infer masses on the order of M200 ~ 8-9 * 10^14 h_70^-1 Msun (Abell 1351) and M200 ~ 5-6 * 10^14 h_70^-1 Msun (Abell 1995). The concentration parameters remain poorly constrained by our weak lensing analysis.