The NuSTAR and Chandra View of CL 0217+70 and Its Tell-tale Radio Halo
Journal
Date Issued
2023
Author(s)
Tümer, Ayşegül
•
Wik, Daniel R.
•
Zhang, Xiaoyuan
•
Hoang, Duy N.
•
•
van Weeren, Reinout J.
•
Rudnick, Lawrence
•
•
Mernier, François
•
Simionescu, Aurora
•
Rojas Bolivar, Randall A.
•
Kraft, Ralph
•
Akamatsu, Hiroki
•
de Plaa, Jelle
Description
We thank the anonymous referee for valuable suggestions
that improved our manuscript. A.T. and D.R.W. acknowledge
support from NASA NuSTAR GO grant No. 80NSSC22K0066
and from NASA ADAP award No. 80NSSC19K1443. M.G.
acknowledges partial support by NASA Chandra GO9-20114X
and HST GO-15890.020/023-A, and the BlackHoleWeather
program. R.J.v.W. acknowledges support from the ERC
Starting Grant ClusterWeb 804208. C.S. acknowledges support
from the MIUR grant FARE “SMS”. A.T. thanks Ross Silver
and Taweewat Somboonpanyakul for valuable discussions.
This research has made use of data from the NuSTAR mission,
a project led by the California Institute of Technology,
managed by the Jet Propulsion Laboratory (JPL), and funded
by by the National Aeronautics and Space Administration
(NASA). In this work, we used the NuSTAR Data Analysis
Software (NuSTARDAS) jointly developed by the ASI Science
Data Center (ASDC, Italy) and the California Institute of
Technology (USA). The data for this research have been
obtained from the High Energy Astrophysics Science Archive
Research Center (HEASARC), provided by NASAs Goddard
Space Flight Center. This research has also made use of data
obtained from the Chandra Data Archive and the Chandra
Source Catalog, and software provided by the Chandra X-ray
Center (CXC) in the application package CIAO.
Abstract
Mergers of galaxy clusters are the most energetic events in the universe, driving shock and cold fronts, generating turbulence, and accelerating particles that create radio halos and relics. The galaxy cluster CL 0217+70 is a remarkable late-stage merger, with a double peripheral radio relic and a giant radio halo. Chandra detects surface brightness (SB) edges that correspond to radio features within the halo. In this work, we present a study of this cluster with Nuclear Spectroscopic Telescope Array and Chandra data using spectro-imaging methods. The global temperature is found to be kT = 9.1 keV. We set an upper limit for the inverse Compton (IC) flux of ~2.7 × 10-12 erg s-1 cm-2, and a lower limit to the magnetic field of 0.08 μG. Our local IC search revealed a possibility that IC emission may have a significant contribution at the outskirts of the radio halo emission and on/near shock regions within ~0.6 r 500 of clusters. We detected a "hot spot" feature in our temperature map coincident with an SB edge, but our investigation on its origin is inconclusive. If the "hot spot" is the downstream of a shock, we set a lower limit of kT > 21 keV to the plasma that corresponds to ${ \mathcal M }$ ~2. We found three shock fronts within 0.5 r 500. Multiple weak shocks within the cluster center hint at an ongoing merger activity and continued feeding of the giant radio halo. CL 0217+70 is the only example hosting these secondary shocks in multiple form.
Volume
942
Issue
79
Start page
1
Issn Identifier
0004-637X
Ads BibCode
2023ApJ...942...79T
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
Tümer_2023_ApJ_942_79.pdf
Description
Pdf editoriale
Size
9.15 MB
Format
Adobe PDF
Checksum (MD5)
24147fe70d6a418c299948263e27244d