Probing Saraswati's heart: evaluating the dynamical state of the massive galaxy cluster A2631 through a comprehensive weak-lensing and dynamical analysis

Abstract

In this work, we investigate the dynamical state of the galaxy cluster Abell 2631, a massive structure located at the core of the Saraswati supercluster. To do this, we first solve a tension found in the literature regarding the weak-lensing mass determination of the cluster. We do this through a comprehensive weak-lensing analysis, exploring the power of the combination of shear and magnification data sets. We find $M_{200}^{\mathrm{wl}}=8.7_{-2.9}^{+2.5}\times 10^{14}$ M${}_{\odot }$. We also determined the mass based on the dynamics of spectroscopic members, corresponding to $M_{200}^{\mathrm{dy}}=12.2\pm 3.0\times 10^{14}$ M${}_{\odot }$, consistent within a 68 per cent CL with the weak-lensing estimate. The scenarios provided by the mass distribution and dynamics of galaxies are reconciled with those provided by X-ray observations in a scenario where A2631 is observed at a late stage of merging.

14 pages, 10 figures, 6 tables. Accepted on Nov, 13 for publication in MNRAS