In order to compute the radial selection functions of the surveys we adopt a Schechter function description of the B_J band luminosity function. In our standard model we adopt the parameters found by Loveday et al for the APM-Stromlo bright galaxy survey, M_* =-19.5, alpha=-0.97 and phi_star=0.014 (Mpc/h)^-3 . We also assume that evolutionary and k-corrections cancel producing a non-evolving luminosity function in the observer frame B_J-band. The figure shows that this simple choice gives reasonable agreement with the observed galaxy number counts at B_J=19.5 and so will produce mock galaxy catalogues with close to the number of galaxies expected in the 2dF survey.
As a variation, we have also produced a selection of mock catalogues in which the artificial assumption that evolutionary and k-corrections cancel has been dropped. For these we use the evolution law k+e= 2.5 log (1+z). This corresponds to weaker luminosity evolution than our standard model. To compensate for this we increase the value of phi_star by 24% to 0.0173 (Mpc/h)^-3 to keep the total number of galaxies in the survey approximately the same as for our standard model.
The redshift distributions predicted by our two models are compared in the figure at the foot of the following page.