Effect of pre-irradiation deformation on thermoluminescence of divalent impurity doped alkali halide crystals

摘要

The effect of pre-irradiation deformation on the thermoluminescence (TL) of alkali halide crystals has been reported. The pre-irradiation deformation causes increase in the thermoluminescence intensity corresponding to both the TL glow peaks of alkali halide crystals. The dependence of TL intensity corresponding to first and second TL peaks on pre-irradiation deformation follows the relations. I_(m_1)=I_(m_1)~O exp (#zeta##epsilon#) and I_(m_1)=I_(m_2)~O exp #zeta##epsilon#. respectively. It is shown that the dislocation debris created during prior deformation of crystals trap the interstitials, which causes decrease in the probability of back reaction.i.c., the recombination between interstitials and vacancies. This results increase in the probability of the formation of stable F-centres. Consequently. for the same radiation doses given to the crystals. The density of F-centres and thereby the TL intensity increases with the pre-irradiation deformation of alkali halide crystals.