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The late merging phase of a galaxy cluster : XMM EPIC Observations of A3266

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 نشر من قبل Jean-Luc Sauvageot
 تاريخ النشر 2005
  مجال البحث فيزياء
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We present a mosaic of five XMM-Newton observations of the nearby ($z=0.0594$) merging galaxy cluster Abell 3266. We use the spectro-imaging capabilities of xmm to build precise (projected) temperature, entropy, pressure and Fe abundance maps. The temperature map exhibits a curved, large-scale hot region, associated with elevated entropy levels, very similar to that foreseen in numerical simulations. The pressure distribution is disturbed in the central region but is remarkably regular on large scales. The Fe abundance map indicates that metals are inhomogeneously distributed across the cluster. Using simple physical calculations and comparison with numerical simulations, we discuss in detail merging scenarios that can reconcile the observed gas density, temperature and entropy structure, and the galaxy density distribution.

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