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arXiv · 1809.01700

The nature of the variable millimetre-selected AGN in the Brightest Cluster Galaxy of Abell 851

R. A. Cheale·J. E. Geach·A. C. Edge·Y. C. Perrott·T. Cantwell
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Abstract

We present the detection of a bright 3mm continuum source in the Brightest Cluster Galaxy (BCG) in Abell 851 (z=0.411) with the NOrthern Extended Millimeter Array (NOEMA). When this detection is compared to other multi-frequency observations across 21cm-100um, including new Arcminute Microkelvin Imager 15GHz observations, we find evidence for a relatively flat, variable core source associated with the BCG. The radio power and amplitude of variability observed in this galaxy is consistent with the cores in lower redshift BCGs in X-ray-selected clusters, and the flat mm-cm spectrum is suggestive of the BCG being a low luminosity AGN archetype. The discovery of this system could provide a basis for a long-term study of the role of low luminosity radio mode 'regulatory' feedback in massive clusters.

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R. A. Cheale, J. E. Geach, A. C. Edge, Y. C. Perrott, T. Cantwell. 2018-09-05. The nature of the variable millimetre-selected AGN in the Brightest Cluster Galaxy of Abell 851. https://doi.org/10.1093/mnrasl/sly161

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