CODEX galaxy clusters catalog

We show that there is no obvious separation of sources on galaxy clusters and AGN, based on distribution of systems on their richness. This is a combination of increasing number of galaxy groups and their selection as identification of an X-ray sources either by chance or due to groups hosting an AGN. To clean the sample, we use a cut on the optical richness at the level corresponding to the 10% completeness of the survey and include it into the modelling of cluster selection function.

We present the X-ray catalog extending to a redshift of 0.6. CODEX is the first large area X-ray selected catalog of Northern clusters reaching the fluxes of 10^-13^ergs/s/cm^2^. We provide the modelling of the sample selection and discuss the redshift evolution of the high end of the X-ray luminosity function (XLF).

Our results on z<0.3 XLF are in agreement with previous studies, while we provide new constraints on the 0.3<z<0.6 XLF. We find a lack of strong redshift evolution of the XLF, provide exact modeling of the effect of low number statistics and AGN contamination and present the resulting constraints on the flat {LAMBDA}CDM.