English: A classical molecular dynamics computer simulation of a collision cascade in Au induced by a 10 keV Au self-recoil. Each small sphere illustrated the position of an atom, in a 2 atom layer thick cross section of a threedimensional simulation cell. The colors are the kinetic energy of the atoms, with white and red being high kinetic energy from 10 keV downwards, and blue being low (on a logarithmic scale). This is relevant to ion and neutron irradiation of materials, for a scientific reference see Nordlund, K., et al. "Defect production in collision cascades in elemental semiconductors and fcc metals." Physical Review B 57.13 (1998): 7556.