A Strong Merger Shock in Abell 665
Date Issued
2016
Author(s)
Dasadia, S.
•
Sun, M.
•
Sarazin, C.
•
Morandi, A.
•
Markevitch, M.
•
Wik, D.
•
Feretti, L.
•
Giovannini, Gabriele
•
•
Abstract
Deep (103 ks) Chandra observations of Abell 665 have revealed rich structures in this merging galaxy cluster, including a strong shock and two cold fronts. The newly discovered shock has a Mach number of M = 3.0 ± 0.6, propagating in front of a cold disrupted cloud. This makes Abell 665 the second cluster, after the Bullet cluster, where a strong merger shock of M ≈ 3 has been detected. The shock velocity from jump conditions is consistent with (2.7 ± 0.7) × 103 km s-1. The new data also reveal a prominent southern cold front with potentially heated gas ahead of it. Abell 665 also hosts a giant radio halo. There is a hint of diffuse radio emission extending to the shock at the north, which needs to be examined with better radio data. This new strong shock provides a great opportunity to study the re-acceleration model with the X-ray and radio data combined.
Volume
820
Issue
1
Start page
L20
Issn Identifier
2041-8205
Ads BibCode
2016ApJ...820L..20D
Rights
open.access