The cluster environments of radio-loud AGN
  Radio-loud AGN play an important r\^ole in galaxy evolution. We need to understand their properties, and the processes that affect their behaviour in order to model galaxy formation and development. We here present preliminary results of an investigation into the cluster environments of radio galaxies. We have found evidence of a strong correlation between radio luminosity and environment richness for low excitation radio galaxies, and no evidence of evolution of the environment with redshift. Conversely, for high excitation radio galaxies, we found no correlation with environment richness, and tentative evidence of evolution of the cluster environment. 
Judith Ineson, Judith Croston, Martin Hardcastle, Ralph Kraft, Daniel   Evans, Matt Jarvis
astro-ph.GA astro-ph.CO