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arXiv · astro-ph/0211230

BeppoSAX observation of the cluster Abell 970

G. B. Lima Neto·H. V. Capelato·L. Sodre Jr·D. Proust
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Abstract

We report new results on the cluster of galaxies Abell 970 obtained from X-ray observation with BeppoSAX. Our analysis of the BeppoSAX MECS and LECS data in the range [0.15-10] keV reveals a mean cluster gas temperature of kT = 4.46_{-0.15}^{+0.14}, a metallicity of Z = 0.31_{-0.04}^{+0.05} Z_\odot, and an interstellar hydrogen absorption density column of N_H = 6.05_{-0.97}^{+1.29} 10^20 cm^-2. Moreover, we obtained azimuthally averaged radial profiles of these quantities. Our results are consistent with the hypothesis that Abell 970 has been disturbed by a past merger or by the ongoing merger process of a substructure, that put the cluster out of equilibrium. This is also demonstrated by the offset between the gas and galaxy distributions. Combining the X-ray data with a recently published analysis of new galaxy radial velocities, we conclude that a subcluster 8 arcmin to the NW is falling into Abell 970 and will merge in a few Gigayears, thus disturbing Abell 970's newly acquired equilibrium. The high alpha-elements/iron ratio that we derive for this cluster supports the hypothesis of early intracluster medium enrichment by Type II supernovae.

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G. B. Lima Neto, H. V. Capelato, L. Sodre Jr, D. Proust. 2002-11-11. BeppoSAX observation of the cluster Abell 970. https://doi.org/10.1051/0004-6361%3A20021656

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