The evolution of radio galaxies at intermediate redshift

Abstract

We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z ∼ 0.4). Photometric redshifts and color selection have been used to select BJ < 23.5 early-type galaxies from the Panoramic Deep Fields, a multicolor survey of two 25 deg2 fields. Approximately 230 radio galaxies have then been selected by matching early-type galaxies with NVSS radio sources brighter than 5 mJy. Estimates of the 1.4 GHz luminosity function of radio galaxies measure significant evolution over the observed redshift range. For an ΩM = 1 cosmology the evolution of the radio power is consistent with luminosity evolution where P(z) ∼ P(0)(1 + z)kL and 3 < kL < ..