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We examine the radio properties of the brightest cluster galaxies (BCGs) in a large sample of X-ray selected galaxy clusters comprising the Brightest Cluster Sample (BCS), the extended BCS and ROSAT-ESO Flux Limited X-ray cluster catalogues. We have multifrequency radio observations of the BCG using a variety of data from the Australia Telescope Compact Array, Jansky Very Large Array and Very Long Baseline Array telescopes. The radio spectral energy distributions of these objects are decomposed into a component attributed to on-going accretion by the active galactic nuclei (AGN) that we refer to as 'the core', and a more diffuse, ageing component we refer to as the 'non-core'. These BCGs are matched to previous studies to determine whether they exhibit emission lines (principally Hα), indicative of the presence of a strong cooling cluster core. We consider how the radio properties of the BCGs vary with cluster environmental factors. Line emitting BCGs are shown to generally host more powerful radio sources, exhibiting the presence of a strong, distinguishable core component in about 60 per cent of cases. This core component more strongly correlates with the BCG's [O III] 5007 Å line emission. For BCGs in line emitting clusters, the X-ray cavity power correlates with both the extended and core radio emission, suggestive of steady fuelling of the AGN over bubble-rise time-scales in these clusters. [ABSTRACT FROM AUTHOR]

ABSTRACT We present new Chandra X-ray observations of the brightest cluster galaxy (BCG) in the cool-core cluster Abell 2597 ( z= 0.0821). 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 Very Large Array radio data. In addition to several possible scenarios, multiwavelength evidence may suggest that the filament is associated with multiphase (103-107 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 modelled 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 outwards by the radio bubble or (b) morphologically and energetically consistent with cavity-driven active galactic nucleus 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. [ABSTRACT FROM AUTHOR]