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Shocks and Bubbles in a Deep Chandra Observation of the Cooling Flow Cluster Abell 2052

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 نشر من قبل Elizabeth L. Blanton
 تاريخ النشر 2009
  مجال البحث فيزياء
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 تأليف E. L. Blanton




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We present results from a deep Chandra observation of Abell 2052. A2052 is a bright, nearby, cooling flow cluster, at a redshift of z=0.035. Concentric surface brightness discontinuities are revealed in the cluster center, and these features are consistent with shocks driven by the AGN, both with Mach numbers of approximately 1.2. The southern cavity in A2052 now appears to be split into two cavities with the southernmost cavity likely representing a ghost bubble from earlier radio activity. There also appears to be a ghost bubble present to the NW of the cluster center. The cycle time measured for the radio source is approximately 2 x 10^7 yr using either the shock separation or the rise time of the bubbles. The energy deposited by the radio source, including a combination of direct shock heating and heating by buoyantly rising bubbles inflated by the AGN, can offset the cooling in the core of the cluster.

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