Physical processes causing limited (<∼1%) energy loss to high-energy particles traversing bulk matter are examined and their cross sections cast in a form suitable for use in Monte Carlo transport calculations. Special attention is paid to scattering off edges. An algorithm is developed, based on the Fermi distribution of multiple Coulomb scattering, which generates first-passage distributions for escaping particles and more generally for transport of particles undergoing multiple scattering in the presence of an edge. Implementation of the various processes and of the edge-scattering algorithm into a Monte Carlo code are briefly indicated. A sample of results obtained with this code is included.

• Received 14 September 1987

DOI:https://doi.org/10.1103/PhysRevD.37.3292