Determination of cosmology and evolution from K-band magnitude-redshift and number count observations

Abstract

We determine cosmological and evolutionary parameters from the 3CR K-band Hubble diagram and K-band number counts, assuming that the galaxies in question undergo pure luminosity evolution. Separately the two data sets are highly degenerate with respect to choice of cosmological and evolutionary parameters, but in combination the degeneracy is resolved. Of models which are either flat or have $Ω_Λ=0$, the preferred ones are close to the canonical case $Ω_\CdM=1$, $Ω_Λ=0$, with luminosity evolution amounting to one magnitude brighter at z=1.