Multi-frequency Radio Observations of the Dissociative Cluster Merger CIZA J0107.7+5408

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Schwartzman, Emma, Clarke, Tracy, Giacintucci, Simona, Peters, Wendy, Randall, Scott, van Weeren, Reinout, Sarkar, Arnab, Rudnick, Lawrence, Blanton, Elizabeth, Finner, Kyle, Mroczkowski, Tony, Nulsen, Paul
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909472567328768
author Schwartzman, Emma
Clarke, Tracy
Giacintucci, Simona
Peters, Wendy
Randall, Scott
van Weeren, Reinout
Sarkar, Arnab
Rudnick, Lawrence
Blanton, Elizabeth
Finner, Kyle
Mroczkowski, Tony
Nulsen, Paul
author_facet Schwartzman, Emma
Clarke, Tracy
Giacintucci, Simona
Peters, Wendy
Randall, Scott
van Weeren, Reinout
Sarkar, Arnab
Rudnick, Lawrence
Blanton, Elizabeth
Finner, Kyle
Mroczkowski, Tony
Nulsen, Paul
contents We present new radio observations of the galaxy cluster merger CIZA J0107.7+5408 (CIZA0107), a large, roughly equal mass, post-core passage, dissociative binary system at z = 0.1066. CIZA0107 is an elongated, disturbed system, hosting two subclusters with optical galaxy number density peaks offset from their associated X-ray density peaks and double-peaked diffuse radio structure. We present new 240-470 MHz and 2.0-4.0 GHz Very Large Array observations of CIZA0107. We image the diffuse emission at high resolution, constrain its integrated spectrum, and map the spectral index distribution. We confirm the presence of steep-spectrum ($α$ $\sim$ -1.3) emission on a scale of about 0.5 Mpc in both subclusters. We identify two smaller ultra-steep spectrum ($α$ $<$ -2) regions, superimposed on larger-scale radio emission associated with the southwestern subcluster. At 340 MHz, we detect a radio edge bounding the emission to the south and show that it is coincident with a weak (M $\sim$ 1.2) shock identified in the Chandra image. At 3 GHz, the emission does not show any corresponding edge-like feature, and in fact it extends beyond the shock. We investigate the nature of the emission in CIZA0107 and find that, while the system may host a double halo structure, we cannot rule out a scenario in which the emission arises from two relics projected on the central cluster regions.
format Preprint
id arxiv_https___arxiv_org_abs_2412_15015
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Multi-frequency Radio Observations of the Dissociative Cluster Merger CIZA J0107.7+5408
Schwartzman, Emma
Clarke, Tracy
Giacintucci, Simona
Peters, Wendy
Randall, Scott
van Weeren, Reinout
Sarkar, Arnab
Rudnick, Lawrence
Blanton, Elizabeth
Finner, Kyle
Mroczkowski, Tony
Nulsen, Paul
Astrophysics of Galaxies
We present new radio observations of the galaxy cluster merger CIZA J0107.7+5408 (CIZA0107), a large, roughly equal mass, post-core passage, dissociative binary system at z = 0.1066. CIZA0107 is an elongated, disturbed system, hosting two subclusters with optical galaxy number density peaks offset from their associated X-ray density peaks and double-peaked diffuse radio structure. We present new 240-470 MHz and 2.0-4.0 GHz Very Large Array observations of CIZA0107. We image the diffuse emission at high resolution, constrain its integrated spectrum, and map the spectral index distribution. We confirm the presence of steep-spectrum ($α$ $\sim$ -1.3) emission on a scale of about 0.5 Mpc in both subclusters. We identify two smaller ultra-steep spectrum ($α$ $<$ -2) regions, superimposed on larger-scale radio emission associated with the southwestern subcluster. At 340 MHz, we detect a radio edge bounding the emission to the south and show that it is coincident with a weak (M $\sim$ 1.2) shock identified in the Chandra image. At 3 GHz, the emission does not show any corresponding edge-like feature, and in fact it extends beyond the shock. We investigate the nature of the emission in CIZA0107 and find that, while the system may host a double halo structure, we cannot rule out a scenario in which the emission arises from two relics projected on the central cluster regions.
title Multi-frequency Radio Observations of the Dissociative Cluster Merger CIZA J0107.7+5408
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2412.15015