An empirical model to form and evolve galaxies in dark matter halos
  Based on the star formation histories (SFH) of galaxies in halos of different
masses, we develop an empirical model to grow galaxies in dark mattet halos.
This model has very few ingredients, any of which can be associated to
observational data and thus be efficiently assessed. By applying this model to
a very high resolution cosmological $N$-body simulation, we predict a number of
galaxy properties that are a very good match to relevant observational data.
Namely, for both centrals and satellites, the galaxy stellar mass function
(SMF) up to redshift $z\simeq4$ and the conditional stellar mass functions
(CSMF) in the local universe are in good agreement with observations. In
addition, the 2-point correlation is well predicted in the different stellar
mass ranges explored by our model. Furthermore, after applying stellar
population synthesis models to our stellar composition as a function of
redshift, we find that the luminosity functions in $^{0.1}u$, $^{0.1}g$,
$^{0.1}r$, $^{0.1}i$ and $^{0.1}z$ bands agree quite well with the SDSS
observational results down to an absolute magnitude at about -17.0. The SDSS
conditional luminosity functions (CLF) itself is predicted well. Finally, the
cold gas is derived from the star formation rate (SFR) to predict the HI gas
mass within each mock galaxy. We find a remarkably good match to observed
HI-to-stellar mass ratios. These features ensure that such galaxy/gas catalogs
can be used to generate reliable mock redshift surveys.
