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A BeppoSAX observation of the merging cluster Abell 3266

Sabrina De Grandi·Silvano Molendi
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Abstract

We present results from a BeppoSAX observation of the rich cluster Abell 3266. The broad band spectrum (2-50 keV) of the cluster, when fitted with an optically thin thermal emission model, yields a temperature of 8.1 +/- 0.2 keV and a metal abundance of 0.17 +/- 0.02 in solar units, and with no evidence of a hard X-ray excess in the PDS spectrum. By performing a spatially resolved spectral analysis we find that the projected temperature drops with increasing radius, going from ~ 10 keV at the cluster core to ~ 5 keV at about 1.5 Mpc. Our BeppoSAX temperature profile is in good agreement with the ASCA temperature profile of Markevitch et al. (1998). From our two-dimensional temperature map we find that the gradient is observed in all azimuthal directions. The temperature gradient may have been caused by a recent merger event also responsible for a velocity dispersion gradient measured in the optical band. The projected metal abundance profile and two-dimensional map are both consistent with being constant.

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Sabrina De Grandi, Silvano Molendi. 1999-10-22. A BeppoSAX observation of the merging cluster Abell 3266. https://doi.org/10.1086/312393

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