Hybrid galaxy formation

We model the two-point correlation function of galaxies in a cold dark matter Universe by combining two powerful theoretical tools - dissipationless N-body simulations of dark matter clustering (specifically the GIF simulations carried out by MPIA and the Virgo Consortium) and semi-analytic modelling of galaxy formation. We construct catalogues of galaxies containing a wide range of information for each galaxy, including magnitudes in various bands, star formation rates, disk and bulge sizes (from the semi-analytic model described by Cole et al 1998) and, importantly, spatial positions and peculiar velocities from the N-body simulation. We then use this information to study the clustering properties of galaxies.