Work

PSZ2 G181.06+48.47. III. Weak-lensing Analysis and Merging Scenario Reconstruction of a Low-mass Cluster with Exceptionally Distant Radio Relics

Year: 2025

Type: article

Abstract: The galaxy cluster PSZ2 G181.06+48.47 ( z = 0.234) is a post-merging system that exhibits symmetric double radio relics separated by ∼2.7 Mpc. We present the first weak-lensing analysis of PSZ2 G181.06+48.47 and propose possible merging scenarios using numerical simulations. Our analysis with Subaru Hyper Suprime-Cam imaging identifies a binary dark matter (DM) structure consisting of northern and southern components, separated by ∼500 kpc. Assuming Navarro–Frenk–White (NFW) halos, the masses for the northern and southern subclusters are M 200 c N = 0.8 8 − 0.30 + 0.35 × 1 0 14 M ⊙ and M 200 c S = 2.7 1 − 0.48 + 0.51 × 1 0 14 M ⊙ , respectively. By superposing the two NFW halos, we determine the total mass of the cluster to be M 200 c = 4.2 2 − 1.00 + 1.10 × 1 0 14 M ⊙ ( M 500 c = 2.9 0 − 0.69 + 0.75 × 1 0 14 M ⊙ ). Our mass estimate suggests that the two relics are located around the cluster R 200 c , where the density of the intracluster medium is very low. Our idealized simulations find that an off-axis collision of a 3:1 major merger can simultaneously reproduce the observed relic and DM halo separations. Fr

Source: The Astrophysical Journal

DOI: 10.3847/1538-4357/adbc99