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ASCA Observations of Temperature Structure and Metal Distribution in the Perseus Cluster of Galaxies

H. Ezawa·N. Y. Yamasaki·T. Ohashi·Y. Fukazawa·M. Hirayama·H. Honda·T. Kamae·K. Kikuchi·R. Shibata
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Abstract

Large-scale distributions of hot-gas temperature and Fe abundance in the Perseus cluster have been studied with multi-pointing observations by the GIS instrument on ASCA. Within a radius of 20' from the cluster center, the energy spectra requires two temperature components, in which the cool component indicates kT ~ 2 keV and the hot-component temperature shows a significant decline from about 8 keV to 6 keV toward the center. In the outer region of the cluster, the temperature shows a fluctuation with an amplitude of about 2 keV and suggest that a western region at ~16' from the cluster center is relatively hotter. As for the Fe abundance, a significant decline with radius is detected from 0.44 solar at the center to ~0.1 solar at a 50' offset region. If observed Fe-K line intensity within 4' from the center is suppressed by a factor of 2 due to the resonance scattering effect, the corrected Fe mass density follows the galaxy distribution. Finally, our results do not support the large-scale velocity gradients previously reported from the same GIS data.

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H. Ezawa, N. Y. Yamasaki, T. Ohashi, Y. Fukazawa, M. Hirayama, H. Honda, T. Kamae, K. Kikuchi, R. Shibata. 2001-05-24. ASCA Observations of Temperature Structure and Metal Distribution in the Perseus Cluster of Galaxies. https://doi.org/10.1093/pasj%2F53.4.595

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