Damped Lyman α systems in galaxy formation simulations

Abstract

We investigate the population of z = 3 damped Lyman systems (DLAs) in a recent series of high-resolution galaxy formation simulations. The simulations are of interest because they form at z = 0 some of the most realistic disc galaxies to date. No free parameters are available in our study: the simulation parameters have been fixed by physical and z = 0 observational constraints, and thus our work provides a genuine consistency test. The precise role of DLAs in galaxy formation remains in debate, but they provide a number of strong constraints on the nature of our simulated bound systems at z = 3 because of their coupled information on neutral H I densities, kinematics, metallicity and estimates of star formation activity.