G. R. Tremblay, C. P. O'Dea, S. A. Baum, T. E. Clarke, C. L. Sarazin, J. N. Bregman, F. Combes, M. Donahue, A. C. Edge, A. C. Fabian, G. J. Ferland, B. R. McNamara, R. Mittal, J. B. R. Oonk, A. C. Quillen, H. R. Russell, J. S. Sanders, P. Salomé, G. M. Voit, R. J. Wilman, M. W. Wise
We present new Chandra X-ray observations of the brightest cluster galaxy (BCG) in the cool core cluster Abell 2597. The data reveal an extensive kpc-scale X-ray cavity network as well as a 15 kpc filament of soft-excess gas exhibiting strong spatial correlation with archival VLA radio data. In addition to several possible scenarios, multiwavelength evidence may suggest that the filament is associated with multiphase (10^3 - 10^7 K) gas that has been entrained and dredged-up by the propagating radio source. Stemming from a full spectral analysis, we also present profiles and 2D spectral maps of modeled X-ray temperature, entropy, pressure, and metal abundance. The maps reveal an arc of hot gas which in projection borders the inner edge of a large X-ray cavity. Although limited by strong caveats, we suggest that the hot arc may be (a) due to a compressed rim of cold gas pushed outward by the radio bubble or (b) morphologically and energetically consistent with cavity-driven active galactic nucleus (AGN) heating models invoked to quench cooling flows, in which the enthalpy of a buoyant X-ray cavity is locally thermalized as ambient gas rushes to refill its wake. If confirmed, this would be the first observational evidence for this model.
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http://arxiv.org/abs/1205.2374
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