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ASCA Measurements of Metallicity and Temperature Distributions in Three Clusters: A4059, MKW 3s and 2A 0335+096

K. Kikuchi·T. Furusho·H. Ezawa·N. Y. Yamasaki·T. Ohashi·Y. Fukazawa·Y. Ikebe
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Abstract

We present ASCA results on the distributions of metallicity and temperature in 3 bright near-by clusters: A4059, MKW 3s and 2A 0335+096. A significant gradient in the metal abundance is detected in A4059, while other clusters suggest similar gradients with low significance. These features together with recent results on AWM 7 and Perseus clusters suggest that metals injected in the ICM are not effectively mixed in the cluster space. Analysis of the GIS data, without explicitly including the cooling flow model, shows no substantial temperature drop at large radii (at half the virial radii) for the 3 systems. This is contrary to the recent results for 30 clusters by Markevitch et al. (1998) who assume rather strong cooling flows. The gas mass fraction of these clusters are 10-15% within 1 Mpc, which suggests that baryonic fraction of about 20% including the stellar mass is a common level in galaxy groups and clusters.

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K. Kikuchi, T. Furusho, H. Ezawa, N. Y. Yamasaki, T. Ohashi, Y. Fukazawa, Y. Ikebe. 1999-03-30. ASCA Measurements of Metallicity and Temperature Distributions in Three Clusters: A4059, MKW 3s and 2A 0335+096. https://doi.org/10.1093/pasj%2F51.3.301

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