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arXiv · 0911.5205

Suzaku Constraints on the Soft and Hard Excess Emissions from Abell 2199

Abstract

The nearby ($z=0.03015$) cluster of galaxies Abell~2199 was observed by Suzaku in X-rays, with five pointings for $\sim 20$ ks each. From the XIS data, the temperature and metal abundance profiles were derived out to $\sim 700$ kpc (0.4 times virial radius). Both these quantities decrease gradually from the center to peripheries by a factor of $\sim 2$, while the oxygen abundance tends to be flat. The temperature within 12' ($\sim 430$ kpc) is $\sim 4$ keV, and the 0.5--10 keV X-ray luminosity integrated up to 30' is $(2.9 \pm 0.1) \times 10^{44}$ erg s$^{-1}$, in agreement with previous XMM-Newton measurements. Above this thermal emission, no significant excess was found either in the XIS range below $\sim 1$ keV, or in the HXD-PIN range above $\sim 15$ keV. The 90%-confidence upper limit on the emission measure of an assumed 0.2 keV warm gas is (3.7--7.5) $\times 10^{62}$ cm$^{-3}$ arcmin$^{-2}$, which is 3.7--7.6 times tighter than the detection reported with XMM-Newton. The 90%-confidence upper limit on the 20--80 keV luminosity of any power law component is $1.8 \times 10^{43}$ erg s$^{-1}$, assuming a photon index of 2.0. Although this upper limit does not reject the possible 2.1$σ$ detection by the BeppoSAX PDS, it is a factor of 2.1 tighter than that of the PDS if both are considered upper limits. The non-detection of the hard excess can be reconciled with the upper limit on diffuse radio emission, without invoking the very low magnetic fields ($< 0.073 μ$G) which were suggested previously.

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BibTeXRIS

Madoka Kawaharada, Kazuo Makishima, Takao Kitaguchi, Sho Okuyama, Kazuhiro Nakazawa, Yasushi Fukazawa. 2009-11-27. Suzaku Constraints on the Soft and Hard Excess Emissions from Abell 2199. https://doi.org/10.1093/pasj%2F62.1.115

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