Extragalactic Jets as Probes of Distant Clusters of Galaxies and the   Clusters Occupied by Bent Radio AGN (COBRA) Survey
  We are conducting a large survey of distant clusters of galaxies using radio sources with bent jets and lobes as tracers. These radio sources are driven by AGN and achieve their bent morphologies through interaction with the surrounding gas found in clusters of galaxies. Based on low-redshift studies, these types of sources can be used to identify clusters very efficiently. We present initial results from our survey of 653 bent-double radio sources with optical hosts too faint to appear in the SDSS. The sample was observed in the infrared with Spitzer, and it has revealed $\sim$200 distant clusters or proto-clusters in the redshift range $z\sim0.7 - 3.0$. The sample of bent-doubles contains both quasars and radio galaxies enabling us to study both radiative and kinetic mode feedback in cluster and group environments at a wide range of redshifts. 
Elizabeth L. Blanton, Rachel Paterno-Mahler, Joshua D. Wing, M. L. N.   Ashby, Emmet Golden-Marx, Mark Brodwin, E. M. Dougla...
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