The High-Redshift Clusters Occupied by Bent Radio AGN (COBRA) Survey [GA]

http://arxiv.org/abs/1611.00746


We present 238 high-redshift galaxy cluster candidates based on galaxy overdensities in the Spitzer/IRAC imaging of the fields surrounding 646 bent, double-lobed radio sources drawn from the Clusters Occupied by Bent Radio AGN (COBRA) Survey. The COBRA sources were chosen as objects in the VLA FIRST survey that lack optical counterparts in the Sloan Digital Sky Survey (SDSS) to a limit of $m_r=22$, making them likely to lie at high redshift. This is confirmed by our observations: the redshift distribution of COBRA sources with estimated redshifts peaks near $z=1$, and extends out to $z\approx3$. Cluster candidates were identified by comparing our sources to a background field and searching for overdensities. Forty-one of these sources are quasars with known spectroscopic redshifts, which may be tracers of some of the most distant clusters known.

Read this paper on arXiv…

R. Paterno-Mahler, E. Blanton, M. Ashby, et. al.
Thu, 3 Nov 16
35/57

Comments: 11 pages, 7 figures, 1 table, Submitted