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

May 2025 • 2025ApJ...984...26A

Authors • Ahn, Eunmo • Cho, Hyejeon • Jee, M. James • Lee, Wonki • Stroe, Andra • Rajpurohit, Kamlesh • Finner, Kyle • Forman, William • Jones, Christine • van Weeren, Reinout

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 and , respectively. By superposing the two NFW halos, we determine the total mass of the cluster to be ( ). Our mass estimate suggests that the two relics are located around the cluster R_200c, 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. From these findings, we suggest that the system is observed ∼0.9 Gyr after the first pericenter passage and is returning from the first apocenter.

Links

• PDF https://iopscience.iop.org/article/10.3847/1538-4357/adbc99/pdf
• PREPRINT http://arxiv.org/abs/2501.09067
• ELECTR https://doi.org/10.3847/1538-4357/adbc99