Simulating the cosmic distribution of neutral hydrogen and its connection with galaxies

Abstract

The neutral hydrogen distribution and its evolution is closely related to various aspects of star formation. This makes understanding and modeling the HI distribution critically important for studying galaxy evolution. The main focus of this thesis is therefore the study of the cosmic distribution of neutral hydrogen using hydrodynamical cosmological simulations. To do this, we combine hydrodynamical cosmological simulations based on the OverWhelmingly Large Simulations (OWLS; Schaye et al. 2010) with accurate radiative transfer, and account for different photoionizing processes. Then, we study the cosmic distribution of HI and its evolution. Furthermore, we study the physical connection between neutral hydrogen and galaxies by analyzing the distribution of HI absorbers with respect to galaxies close to them.