  In the local Universe, high-power radio galaxies live in lower density
environments than low-luminosity radio galaxies. If this trend continues to
higher redshifts, powerful radio galaxies would serve as efficient probes of
moderate redshift groups and poor clusters. Photometric studies of radio
galaxies at 0.3 < z < 0.5 suggest that the radio luminosity-environment
correlation disappears at moderate redshifts, though this could be the result
of foreground/background contamination affecting the photometric measures of
environment. We have obtained multi-object spectroscopy of in the fields of 14
lower luminosity (L_1.4GHz < 4x10^24 W/Hz) and higher luminosity (L_1.4GHz >
1.2x10^25 W/Hz) radio galaxies at z ~ 0.3 to spectroscopically investigate the
link between the environment and the radio luminosity of radio galaxies at
moderate redshifts. Our results support the photometric analyses; there does
not appear to be a correlation between the luminosity of a radio galaxy and its
environment at moderate redshifts. Hence, radio galaxies are not efficient
signposts for group environments at moderate redshifts.

Astrophysics