FIRST J011527.4+000005 , the SIMBAD biblio

Radio galaxies are uniquely useful as probes of large-scale structure since their uniform identification with giant elliptical galaxies out to high redshift means that the evolution of their bias factor can be predicted. As the initial stage in a project to study large-scale structure with radio galaxies, we have performed a small redshift survey, selecting 29 radio galaxies in the range of 0.19<z<0.45 from a contiguous 40 deg² area of sky. We detect significant clustering within this sample. The amplitude of the two-point correlation function that we measure is consistent with no evolution from the local (z<0.1) value. This is as expected in a model in which radio galaxy hosts form at high redshift and thereafter obey a continuity equation, although the signal-to-noise ratio of the detection is too low to rule out other models. Larger surveys out to z∼1 should reveal the structures of superclusters at intermediate redshifts and should strongly constrain models for the evolution of large-scale structure.