Computer simulation models for the slowing down of energetic atoms in matter are often based on the binary collision approximation (BCA). Such models typically ignore the temporal aspects of the problem. A method is described whereby calculations of the times at which energetic particles reach their collision points may be included in such BCA simulations without altering the ‘‘event-driven’’ structure of the model. The enhanced model is illustrated by calculations of the time required by 10-eV to 10-keV Cu atoms to slow down in both crystalline and amorphous Cu targets. In addition to the mean slowing-down time, distributions of slowing-down times and correlations between slowing-down times and particle ranges are presented. The utility of range-time correlations in studying penetration problems is demonstrated.

• Received 22 March 1989

DOI:https://doi.org/10.1103/PhysRevB.40.10717