Red galaxy overdensities and the varied cluster environments of powerful radio sources with z~1.6

  title={Red galaxy overdensities and the varied cluster environments of powerful radio sources with z~1.6},
  author={P.N.Best and M.D.Lehnert and George K. Miley and H. J. A. Rottgering},
  journal={Monthly Notices of the Royal Astronomical Society},
The environments of a complete subsample of six of the most powerful radio-loud active galactic nuclei (AGN) at redshifts z ∼ 1.6 are investigated, using deep RJK imaging to depths of R ∼ 26, J ∼ 22.4 and K ∼ 20.6. An excess of galaxy counts in the K band is seen across these fields; these surplus galaxy counts are predominantly associated with red galaxies (R − K 4) of magnitudes 17.5 K 20.5 found within radial distances of ∼1 Mpc of the AGN host. These are exactly (though not uniquely) the… 
Galaxy protocluster candidates around z∼ 2.4 radio galaxies
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Deep CCD imaging at the Isaac Newton Telescope provided a sample of '" 7000 faint galaxies, with B - R colours, to faint limits of B ~ 25.5 mag and R ~ 24.5 mag. The number counts of these galaxies
Further Evidence for a Change in the Cluster Environments of Radio Galaxies with Cosmic Epoch
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