Evaluation of hyperfine interactions in strontium titanate perovskite for low doses of electron beam radiation

Perovskite are potential crystalline host phases for immobilization of actinides and fission products generated in nuclear reactor fuel. Crystalline matrix undergoes radiation damage from radiations emanating from immobilized radioactive waste. This may influence the hyperfine interactions in host crystalline matrices. Hyperfine interactions in strontium titanate perovskite have been studied for low doses of β radiation induced local structural changes (if any) using γ - γ Time Differential Perturbed Angular Correlation (TDPAC) spectroscopy using 181 Hf as a probe. Samples were irradiated with external electron beam source to simulate beta radiation effects in the matrix. TDPAC spectrum of unirradiated strontium titanate revealed the probe experiencing two sites shown by a dynamic component and a static component of Electric Field Gradient (EFG). Samples were irradiated with electron beam up to a dose of 50 kGy. TDPAC results of irradiated strontium titanate matrix do not show any change in static hyperfine interaction parameters. The dynamic component was found to be affected after irradiation as evident from the increase in the relaxation time ( τ ) for irradiated samples compared to unirradiated sample. However, no change in τ -value was observed with the increasing irradiation dose.