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arXiv · 2311.00643

Weak-Lensing Analysis of the Complex Cluster Merger Abell 746 with Subaru/Hyper Suprime-Cam

Kim HyeongHan·Hyejeon Cho·M. James Jee·David Wittman·Sangjun Cha·Wonki Lee·Kyle Finner·Kamlesh Rajpurohit·Marcus Brüggen·William Forman·Christine Jones·Reinout van Weeren·Andrea Botteon·Lorenzo Lovisari·Andra Stroe·Paola Domínguez-Fernández·Ewan O'Sullivan·Jan Vrtilek
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Abstract

The galaxy cluster Abell 746 (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 $M_{500}=4.4\pm1.0\times10^{14}~M_{\odot}$ is consistent with the previous results from SZ 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.

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Kim HyeongHan, Hyejeon Cho, M. James Jee, David Wittman, Sangjun Cha, Wonki Lee, Kyle Finner, Kamlesh Rajpurohit, Marcus Brüggen, William Forman, Christine Jones, Reinout van Weeren, Andrea Botteon, Lorenzo Lovisari, Andra Stroe, Paola Domínguez-Fernández, Ewan O'Sullivan, Jan Vrtilek. 2023-11-01. Weak-Lensing Analysis of the Complex Cluster Merger Abell 746 with Subaru/Hyper Suprime-Cam. https://doi.org/10.3847/1538-4357/ad1bcc

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