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This content will become publicly available on March 1, 2026

Title: Weak-lensing Characterization of the Dark Matter in 29 Merging Clusters that Exhibit Radio Relics
We present a multiwavelength analysis of 29 merging galaxy clusters that exhibit radio relics. For each merging system, we perform a weak-lensing analysis on Subaru optical imaging. We generate high-resolution mass maps of the dark matter distributions, which are critical for discerning the merging constituents. Combining the weak-lensing detections with X-ray emission, radio emission, and galaxy redshifts, we discuss the formation of radio relics from the past collision. For each cluster, we obtain mass estimates by fitting a multicomponent Navarro–Frenk–White model with and without a concentration–mass relation. We compare the mass estimates of each subcluster to their velocity dispersion measurements and find that they preferentially lie below the expected velocity dispersion scaling relation, especially at the low-mass end (∼1014M⊙). We show that the majority of the clusters that exhibit radio relics are in major mergers with a mass ratio below 1:4. We investigate the position of the mass peak relative to the galaxy luminosity peak, number density peak, and brightest cluster galaxy (BCG) locations and find that the BCG tends to better trace the mass peak position. Finally, we update a golden sample of eight galaxy clusters that have the simplest geometries and can provide the cleanest picture of the past merger, which we recommend for further investigation to constrain the nature of dark matter and the acceleration process that leads to radio relics.  more » « less
Award ID(s):
2308383
PAR ID:
10598150
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal Supplement Series
Volume:
277
Issue:
1
ISSN:
0067-0049
Page Range / eLocation ID:
28
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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