Hiroki Akamatsu, Hajime Kawahara
We perform a systematic X-ray analysis of six giant radio relics of four
clusters with Suzaku satellite by compiling new analysis of CIZA 2242.8-5301,
Zwcl 2341.1-0000, and Abell 3667 and previous results of A3667 and A3376.
Especially we first observed the narrow (~50 kpc) relic of CIZA 2242.8-5301 by
Suzaku satellite, which enable us to reduce the projection effect. From the
spectroscopic temperature profiles across the relic, we find that temperature
profiles exhibits significant jumps across the relics for CIZA 2242.8-5301,
A3376, A3667NW and A3667SE. We evaluated the Mach number from X-ray temperature
or pressure with the Rankine-Hugoniot jump condition and compared with the Mach
number from radio spectrum index. The resultant Mach numbers (M= 1.5-3) are
almost consistent with each other, while the Mach number of CIZA2242 from X-ray
tends to be lower than that of the radio observation. These results of the
systematic analysis can be interpreted as the giant radio relics in merging
clusters being related to the strong shock structure, as suggested by previous
studies of the analysis of an individual cluster. We also discuss the non
equilibrium state of the electron temperature and the average temperature at
the radio relic.
View original:
http://arxiv.org/abs/1112.3030
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