Oxidative degradation of CR-39 track detector in the surface region during gamma-irradiation

To explain the previously observed changes in the bulk etching property of CR-39 induced by gamma or high-energy electron irradiation, both a mass balance equation for the radicals, the active sites by irradiation, and a diffusion equation for the dissolved oxygen were applied to calculate the damage distribution in depth. The depth distribution of the damage in gamma-irradiated CR-39 was interpreted as a result of the exhaust of the dissolved oxygen in the deeper layer. The present calculations and the previous experiments imply that latent tracks in CR-39 are also produced through the local oxidation process along the ion path. (author)