Evolution in the clustering strength of radio galaxies
  We cross match the NVSS and FIRST surveys with three large photometric
catalogues of luminous red galaxies (LRGs) to define radio-loud samples. These
have median redshifts 0.35, 0.55 and 0.68 and, by matching rest-frame optical
and radio properties, we construct uniform samples across the three surveys.
This paper is concerned with the clustering properties of these samples derived
from the angular correlation function. The primary aim is to characterise any
evolution in the clustering amplitude of radio galaxies bellow z~0.68.
  We find no evidence for evolution in the large-scale (~1-50h^{-1}Mpc)
clustering amplitude. Our radio galaxy autocorrelations are consistent with
previous findings indicating little-to-no evolution in the redshift range 0.68
to 0 (~6Gyr of time). We also cross correlate radio galaxies with the parent
LRG samples to increase the precision of our results and again find no evidence
for evolution. Our results are inconsistent with a long-lived model for the
clustering evolution that assumes radio sources randomly sample the LRG
population. A model where the halo mass is constant with redshift is consistent
with the data. This is similar to QSOs that have clustering amplitudes
consistent with a single halo mass at all redshifts. Given that the brightest
radio sources show stronger evolution in space density compared to fainter
radio sources we restrict our samples to include only objects with
L>10^{26}W/Hz and repeat the analysis. Again we find no evidence for evolution
in the comoving correlation amplitude. These radio sources appear to inhabit
the same mass halos as fainter radio galaxies (~9x10^{13}h^{-1}M_\odot). These
halos are ~twice as massive as those of the general LRG population and ~30
times as massive as optical AGN/QSOs.
