Weak-lensing Analysis of the Complex Cluster Merger A746 with Subaru/Hyper Suprime-Cam

Abstract

The galaxy cluster A746 ( z = 0.214), featuring a double radio relic system, two isolated radio relics, a possible radio halo, disturbed V-shaped X-ray emission, and intricate galaxy distributions, is a unique and complex merging system. We present a weak-lensing analysis of A746 based on wide-field imaging data from Subaru/Hyper Suprime-Cam observations. The mass distribution is characterized by a main peak, which coincides with the center of the X-ray emission. At this main peak, we detect two extensions toward the north and west tracing the cluster galaxy and X-ray distributions. Despite the ongoing merger, our estimate of the A746 global mass M _500 = 4.4 ± 1.0 × 10 ^14 M _⊙ is consistent with the previous results from Sunyaev-Zel'dovich and X-ray observations. We conclude that reconciling the distributions of mass, galaxies, and intracluster medium with the double radio relic system and other radio features remains challenging.

Keywords

• Abell clusters
• Galaxy clusters
• Weak gravitational lensing