Mergers of collisionless systems

The hierarchical clustering scenario is examined by merging haloes of collisionless particles under controlled conditions. Each simulation contains 16 000 particles, which gives a finer spatial resolution than in previous work. We find that dark matter haloes can grow homologously, obeying simple scaling laws. All the mergers tend towards a single density profile, which in our case closely resembles that given by de Vaucouleurs. The high …