The study on the kinetic parameters of deep traps of α-Al2O3:C (TLD-500) dosimeter by comparing experimental photo-transferred thermoluminescence response with the theoretical model

Abstract

Photo-transferred thermoluminescence (PTTL) response of α-Al₂O₃:C (TLD-500) was fitted to the theoretical PTTL model. It was found that, the area under the PTTL glow curve depends only on the population of charge carriers in the active traps and the numbers of active traps does not affect the PTTL glow curve area. Further more, the deep trapping states in this phosphor depopulate at high temperatures and it is not possible to obtain their kinetic parameters directly, as by increasing the temperature, the peaks in the glow curve are affected by the thermal quenching effect (decrease in TL glow curve at increased temperature due to non-radiative transitions). In this work, the experimental PTTL responses obtained for different absorbed doses were fitted to the theoretical PTTL ones. Thus, the kinetic parameters of deep traps were obtained by comparing the responses generated by the model with the experimental results. The PTTL glow curve of TLD-500 is of importance since it can be used to re-estimate the absorbed dose, UV dosimetry and dating.