Gamma displacement cross-sections in various materials

The gamma displacement cross-sections for energies up to 14 MeV have been calculated in various materials at two values of displacement threshold energy (24 and 40 eV). Three types of gamma ray interactions with materials are considered, the photoelectric effect, Compton scattering and pair production. Depending on the atomic number (Z) of target materials and energy of incident gamma rays, the relative contribution of three interactions to total displacements changes. It is found that for medium and low-Z material Compton scattering is predominant over most of the energy range, while pair production becomes important for high-Z material at high gamma energy.