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تسجيل مستخدم جديدDeep Chandra Observations of Abell 2199: the Interplay between Merger-Induced Gas Motions and Nuclear Outbursts in a Cool Core Cluster
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Paul E. J. Nulsen
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We present new Chandra observations of Abell 2199 that show evidence of gas sloshing due to a minor merger, as well as impacts of the radio source, 3C 338, hosted by the central galaxy, NGC 6166, on the intracluster gas. The new data are consistent with previous evidence of a Mach 1.46 shock 100 from the cluster center, although there is still no convincing evidence for the expected temperature jump. Other interpretations of this feature are possible, but none is fully satisfactory. Large scale asymmetries, including enhanced X-ray emission 200 southwest of the cluster center and a plume of low entropy, enriched gas reaching 50 to the north of the center, are signatures of gas sloshing induced by core passage of a merging subcluster about 400 Myr ago. An association between the unusual radio ridge and low entropy gas are consistent with this feature being the remnant of a former radio jet that was swept away from the AGN by gas sloshing. A large discrepancy between the energy required to produce the 100 shock and the enthalpy of the outer radio lobes of 3C 338 suggests that the lobes were formed by a more recent, less powerful radio outburst. Lack of evidence for shocks in the central 10 indicates that the power of the jet now is some two orders of magnitude smaller than when the 100 shock was formed.
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