Calculation of charges near an interface of dissimilar media under gamma irradiation

A semiempirical model is described of charge deposition near an interface of dissimilar materials irradiated by γ-quanta. The input to the suggested model is the secondary electron yield and effective reflection coefficient. These parameters were tabulated using a special Monte Carlo code for Z=6-79 (C, Al, Cu, Ag, Au) and for different initial angles of photons with energy 0.1-2 MeV. It is found that energy and particle reflection coefficients differ by the factor of approximately 1.5. The deposited charge calculated according to the model agrees with that obtained by direct simulation technique to an accuracy better than 10% for every combination of materials in the energy range considered