Mergers and the Formation of Disk Galaxies in Hierarchically Clustering Universes

Abstract

It is commonly accepted, that galaxies acquire their angular momentum from tidal torques due to surrounding matter (Hoyle 1949). Most of the angular momentum is gained during the linear phase of the collapse (White 1984). After the turnaround point is reached, any further gain of angular momentum is strongly suppressed because it is increasingly difficult for the tidal field to act on the shrinking radius of the forming dark halo.