The Mass Of The Coma Cluster From Weak Lensing In The Sloan Digital Sky Survey

TL;DR

This paper measures the mass of the Coma Cluster using weak lensing data from SDSS, providing a precise mass estimate that agrees with dynamical methods, and is notable for its low redshift and large angular coverage.

Contribution

First weak lensing mass measurement of the Coma Cluster at low redshift using SDSS data, with a detailed comparison to dynamical mass estimates.

Findings

Virial radius r_{200}=1.99_{-0.22}^{+0.21}h^{-1}Mpc

Virial mass M_{200}=1.88_{-0.56}^{+0.65}×10^{15}h^{-1}M_{\u00b7

Weak lensing measurement agrees with dynamical estimates.

Abstract

We present a weak lensing analysis of the Coma Cluster using the Sloan Digital Sky Survey (SDSS) Data Release Five. Complete imaging of a ~ 200 square degree region is used to measure the tangential shear of this cluster. The shear is fit to an NFW model and we find a virial radius of r_{200}=1.99_{-0.22}^{+0.21}h^{-1}Mpc which corresponds to a virial mass of M_{200}=1.88_{-0.56}^{+0.65}\times10^{15}h^{-1}M_{\odot}. We additionally compare our weak lensing measurement to the virial mass derived using dynamical techniques, and find they are in agreement. This is the lowest redshift, largest angle weak lensing measurement of an individual cluster to date.