An algorithm to build mock galaxy catalogues using MICE simulations
  We present a method to build mock galaxy catalogues starting from a halo
catalogue that uses halo occupation distribution (HOD) recipes as well as the
subhalo abundance matching (SHAM) technique. Combining both prescriptions we
are able to push the absolute magnitude of the resulting catalogue to fainter
luminosities than using just the SHAM technique and can interpret our results
in terms of the HOD modelling. We optimize the method by populating with
galaxies friends-of-friends dark matter haloes extracted from the Marenostrum
Institut de Ci\`{e}ncies de l'Espai (MICE) dark matter simulations and
comparing them to observational constraints. Our resulting mock galaxy
catalogues manage to reproduce the observed local galaxy luminosity function
and the colour-magnitude distribution as observed by the Sloan Digital Sky
Survey. They also reproduce the observed galaxy clustering properties as a
function of luminosity and colour. In order to achieve that, the algorithm also
includes scatter in the halo mass - galaxy luminosity relation derived from
direct SHAM and a modified NFW mass density profile to place satellite galaxies
in their host dark matter haloes. Improving on general usage of the HOD that
fits the clustering for given magnitude limited samples, our catalogues are
constructed to fit observations at all luminosities considered and therefore
for any luminosity subsample. Overall, our algorithm is an economic procedure
of obtaining galaxy mock catalogues down to faint magnitudes that are necessary
to understand and interpret galaxy surveys.
