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A BeppoSAX observation of the merging cluster Abell 3266

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 نشر من قبل Sabrina De Grandi
 تاريخ النشر 1999
  مجال البحث فيزياء
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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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