Hyperfine interaction study in gamma irradiated crystalline waste form matrix (CaTiO₃) using perturbed angular correlation spectroscopy

Ceramics are being studied as alternative matrices for immobilization of the high level liquid waste generated during the reprocessing of spent nuclear fuels, owing to their higher thermodynamic stability compared to glasses. Self irradiation from immobilized fission products may result in phase transformation or metamictization which in turn may affect the physical and chemical durability of the waste form. Present work aimed to study change in hyperfine interactions at probing site as function of γ-irradiation doses. Any change in local structure of crystalline matrix due to accumulated gamma dose would reflect in hyperfine interactions present at site. These hyperfine interactions can be observed by Perturbed Angular Correlation (PAC) spectroscopy. In this study, Calcium Titanate (CTO) matrix has been studied for local structural changes for high doses of gamma radiation using PAC spectroscopy