Perseus cluster in its X-ray entirety with SRG/eROSITA. Merger and Radio-Uroboroses

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Churazov, Eugene, Khabibullin, Ildar, Lyskova, Natalya, Sunyaev, Rashid, Dolag, Klaus
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918406836453376
author Churazov, Eugene
Khabibullin, Ildar
Lyskova, Natalya
Sunyaev, Rashid
Dolag, Klaus
author_facet Churazov, Eugene
Khabibullin, Ildar
Lyskova, Natalya
Sunyaev, Rashid
Dolag, Klaus
contents The Perseus cluster (Abell 426) is a nearby massive galaxy cluster that spans several degrees. We combined SRG/eROSITA, XMM-Newton, and Chandra data to get a complete coverage of this cluster in X-rays up to $R_{\rm 200c}$ and beyond, although at the largest radii, spatial non-uniformities of the X-ray sky background and foreground dominate. While the Perseus central part represents a canonical cool-core structure with clear signs of AGN Feedback, the outskirts, in turn, serve as a convincing example of a merger-perturbed system. X-ray data suggest that IC310 is the main galaxy of a subcluster that merges with Perseus over the past $\sim 4\,{\rm Gyr}$. Overall, this configuration resembles the merger between the Coma cluster and the NGC4839 group. It is statistically more likely to find a merging group near the apocenter of its orbit. Therefore, it is not surprising that IC310 in Perseus has a relatively small velocity relative to the main cluster, similarly to NGC4839 in Coma. Perseus also hosts a high-velocity radio galaxy, NGC1265 (line-of-sight velocity is almost twice the virial velocity of the main cluster), which is known for its spectacular radio tail. Unless this galaxy has been accelerated by a time-variable potential associated with the merger, it has to move almost along the line of sight through the entire cluster, which would be a rare, but not a truly exceptional configuration. Both galaxies, IC310 and NGC1265, have remarkable radio tails with sharp bends that are reminiscent of a "snake biting its tail". We speculate that these curious shapes are natural consequences of their (different) orbits in Perseus. For IC310, the proximity to the apocenter and the reversal of its radial velocity might play a role. For NGC1265, the nearly line-of-sight motion coupled with the gas motions in the merging system might be important.
format Preprint
id arxiv_https___arxiv_org_abs_2507_19987
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Perseus cluster in its X-ray entirety with SRG/eROSITA. Merger and Radio-Uroboroses
Churazov, Eugene
Khabibullin, Ildar
Lyskova, Natalya
Sunyaev, Rashid
Dolag, Klaus
High Energy Astrophysical Phenomena
The Perseus cluster (Abell 426) is a nearby massive galaxy cluster that spans several degrees. We combined SRG/eROSITA, XMM-Newton, and Chandra data to get a complete coverage of this cluster in X-rays up to $R_{\rm 200c}$ and beyond, although at the largest radii, spatial non-uniformities of the X-ray sky background and foreground dominate. While the Perseus central part represents a canonical cool-core structure with clear signs of AGN Feedback, the outskirts, in turn, serve as a convincing example of a merger-perturbed system. X-ray data suggest that IC310 is the main galaxy of a subcluster that merges with Perseus over the past $\sim 4\,{\rm Gyr}$. Overall, this configuration resembles the merger between the Coma cluster and the NGC4839 group. It is statistically more likely to find a merging group near the apocenter of its orbit. Therefore, it is not surprising that IC310 in Perseus has a relatively small velocity relative to the main cluster, similarly to NGC4839 in Coma. Perseus also hosts a high-velocity radio galaxy, NGC1265 (line-of-sight velocity is almost twice the virial velocity of the main cluster), which is known for its spectacular radio tail. Unless this galaxy has been accelerated by a time-variable potential associated with the merger, it has to move almost along the line of sight through the entire cluster, which would be a rare, but not a truly exceptional configuration. Both galaxies, IC310 and NGC1265, have remarkable radio tails with sharp bends that are reminiscent of a "snake biting its tail". We speculate that these curious shapes are natural consequences of their (different) orbits in Perseus. For IC310, the proximity to the apocenter and the reversal of its radial velocity might play a role. For NGC1265, the nearly line-of-sight motion coupled with the gas motions in the merging system might be important.
title Perseus cluster in its X-ray entirety with SRG/eROSITA. Merger and Radio-Uroboroses
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2507.19987