Role of radical ions in the thermally stimulated luminescence of uranium doped BaCO3 system

Abstract

Electron paramagnetic resonance (EPR) studies of γ-irradiated uranium doped BaCO3 have shown the formation of CO3−, CO2−, O3− and O2− ions. Thermally stimulated luminescence (TSL) glow curves of the γ-irradiated samples in the 300–600 K range have exhibited an intense peak around 360 K and a weak one around 440 K. The trap parameters for these peaks have been determined from TSL data. Spectral studies of the glow have revealed emission around 566, 583 and 590 nm characteristic of the uranate ion. From studies on the thermal stabilities of the radical ions, it has been inferred that the glow peak around 360 K is associated with the thermal destruction of O2− ion and the peak around 440 K is associated with the thermal destruction of CO3− ion.