Left: Distribution of the ratio, v_c/v_e, for all clump-clump (non-collapsed objects only) collisions (see text Sect. 5.9.1) Right: Distribution of the impact angle, θ, for all clump–clump collisions. The solid orange line shows only collisions between clumps, while the thin dotted black lines shows those between collapsed objects. The expected distribution for random orientations (dotted red line) as well as for a flat system (dashed green line) are also shown. Further explanations are given in Sect. 5.9.2.