PREIRRADATION AND POSTIRRADIATION DEFORMATION EFFECTS ON THE THERMOLUMINESCENCE OF KCLY CRYSTALS

The thermoluminescence (TL) behaviour of X-irradiated KCl crystals con taining yttrium have been investigated as a function of plastic deform ation, both prior to and subsequent to irradiation. In the crystals su bjected to deformation prior to irradiation, the TL intensity is found to increase with the amount of plastic deformation whereas in those s ubjected to deformation subsequent to irradiation, the same is observe d to decrease. A new high temperature glow peak is also found to grow due to the plastic deformation before irradiation. These results are e xplained on the basis of various processes of point and line defect in teractions; such as creation, modification and annihilation of traps b y moving dislocations, etc.; that take place during the plastic deform ation of the crystal.