IDCS J1426.5+3508: Weak Lensing Analysis of a Massive Galaxy Cluster at $z=1.75$

TL;DR

This study conducts a weak lensing analysis of the most distant galaxy cluster at redshift 1.75, deriving its mass and confirming its consistency with lower-redshift scaling relations, thus providing insights into cluster evolution.

Contribution

First weak lensing mass measurement of a galaxy cluster at z=1.75, confirming the mass and scaling relations at high redshift.

Findings

Mass estimate of $2.3^{+2.1}_{-1.4} imes 10^{14} M_ ext{sun}$

Cluster mass aligns with low-redshift scaling relations

Minimal evolution observed in SZ-weak lensing relation

Abstract

We present a weak lensing study of the galaxy cluster IDCS J1426.5+3508 at $z=1.75$, which is the highest redshift strong lensing cluster known and the most distant cluster for which a weak lensing analysis has been undertaken. Using F160W, F814W, and F606W observations with the Hubble Space Telescope, we detect tangential shear at $2\sigma$ significance. Fitting a Navarro-Frenk-White mass profile to the shear with a theoretical median mass-concentration relation, we derive a mass $M_{200,\mathrm{crit}}=2.3^{+2.1}_{-1.4}\times10^{14}$ M$_{\odot}$. This mass is consistent with previous mass estimates from the Sunyaev-Zel'dovich (SZ) effect, X-ray, and strong lensing. The cluster lies on the local SZ-weak lensing mass scaling relation observed at low redshift, indicative of minimal evolution in this relation.