Exemplary Merging Clusters: Weak-lensing and X-Ray Analysis of the Double Radio Relic, Merging Galaxy Clusters MACS J1752.0+4440 and ZWCL 1856.8+6616

Journal Article · 09 September 2021 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/ac0d00 · OSTI ID:1873625

Finner, Kyle  ^[1]; HyeongHan, Kim  ^[1]; Jee, M. James  ^[2]; Wittman, David  ^[3]; Forman, William R.  ^[4]; van Weeren, Reinout J.  ^[5]; Golovich, Nathan R.  ^[6]; Dawson, William A.  ^[6]; Jones, Alexander  ^[7]; de Gasperin, Francesco  ^[7]; Jones, Christine  ^[4]

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1. Yonsei University, Seoul (Korea, Republic of)
2. Yonsei University, Seoul (Korea, Republic of); University of California, Davis, CA (United States)
3. University of California, Davis, CA (United States)
4. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
5. Leiden University (Netherlands)
6. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
7. University of Hamburg (Germany)

We report the investigation of merging galaxy clusters that exhibit radio relics is strengthening our understanding of the formation and evolution of galaxy clusters, the nature of dark matter, the intracluster medium, and astrophysical particle acceleration. Each merging cluster provides only a single view of the cluster formation process, and the variety of merging clusters is vast. Clusters hosting double radio relics are rare and extremely important because they allow tight constraints on the merger scenario. We present a weak-lensing and X-ray analysis of MACS J1752.0+4440 (z = 0.365) and ZWCL 1856.8+6616 (z = 0.304), two double radio relic clusters. Our weak-lensing mass estimates show that each cluster is a major merger with approximately 1:1 mass ratio. The total mass of MACS J1752.0+4440 (ZWCL 1856.8+6616) is M₂₀₀ =14.7 $$_{-3.3}+{+3.8}$$ x 10¹⁴ M_⊙ M²⁰⁰ = 2.4 $$_{-0.7}^{+0.9}$$ 10¹⁴ M_⊙). We find that these two clusters have comparable features in their weak-lensing and gas distributions, even though the systems have vastly different total masses. From the likeness of the X-ray morphologies and the remarkable symmetry of the radio relics, we propose that both systems underwent nearly head-on collisions. However, revelations from the hot-gas features and our multiwavelength data analysis suggest that ZWCL 1856.8+6618 is likely at a later merger phase than MACS J1752.0+4440. We postulate that the SW radio relic in MACS J1752.0+4440 is a result of particle reacceleration.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); National Research Foundation of Korea; National Aeronautics and Space Administration (NASA)
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 1873625
• Report Number(s): LLNL-JRNL-835395; 1054401
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 918; ISSN 0004-637X
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English