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arXiv · 0708.1265

Evolution of a Powerful Radio Loud Quasar 3C186 and its Impact on the Cluster Environment at z=1

Abstract

X-ray cluster emission has been observed mainly in clusters with "inactive" cD galaxies (L_bol ~1E40-1E43erg/sec), which do not show signs of accretion onto a SMBH. Our recent Chandra discovery of ~100kpc scale diffuse X-ray emission revealed the presence of an X-ray cluster associated with the radio loud quasar 3C186 at redshift z=1.1 and suggests interactions between the quasar and the cluster. In contrast to the majority of X-ray clusters the 3C186 cluster contains a quasar in the center whose radiative power alone exceeds that which would be needed to quench the cluster cooling. We present the Chandra X-ray data and new deep radio and optical images of this cluster. The 3C186 quasar is a powerful Compact Steep Spectrum radio source expanding into the cluster medium. The 2arcsec radio jet is unresolved in the Chandra observation, but its direction is orthogonal to the elliptical surface brightness of the cluster. The radio data show the possible presence of old radio lobes on 10 arcsec scale in the direction of the radio jet. We discuss the nature of this source in the context of intermittent radio activity and the interaction of the young expanding radio source with the cluster medium.

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Aneta Siemiginowska, Thomas L. Aldcroft, Doug Burke, Jill Bechtold, C. C. Cheung, Stephanie LaMassa, Diana M. Worrall. 2007-08-09. Evolution of a Powerful Radio Loud Quasar 3C186 and its Impact on the Cluster Environment at z=1. https://arxiv.org/abs/0708.1265

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