Physical properties of simulated galaxy populations at z=2 - II. Effects of cosmology, reionization and ISM physics

Understand

We use hydrodynamical simulations from the OWLS project to investigate the dependence of the physical properties of galaxy populations at redshift 2 on the assumed star formation law, the equation of state imposed on the unresolved interstellar medium, the stellar initial mass function, the reionization history, and the assumed cosmology.

• This work complements that of Paper I, where we studied the effects of varying models for galactic winds driven by star formation and AGN.
• The normalisation of the matter power spectrum strongly affects the galaxy mass function, but has a relatively small effect on the physical properties of galaxies residing in haloes of a fixed mass.
• Reionization suppresses the stellar masses and gas fractions of low-mass galaxies, but by z = 2 the results are insensitive to the timing of reionization.