The analysis of thermoluminescent glow peaks of CaF₂ : Dy (TLD-200) after β-irradiation

Variable dose (VD), T_m–T_stop, initial rise (IR), variable heating rate (VHR), peak shape (PS) and computerized glow curve deconvolution (CGCD) methods are used to determine the number of peaks, the order of kinetics (b), the activation energy (E_a) and attempt-to-escape frequency (s) associated with the glow peaks in CaF₂ : Dy (TLD-200) after β-irradiation between the dose level 0.1 and 110 Gy. The T_m–T_stop procedure indicates that the glow curve of this crystal consists of at least nine glow peaks. The dose variation experiment indicates that seven of them, namely peaks 1–6 and 8, are of first-order kinetics and peaks 7 and 9 are of general-order kinetics. However, the T_m–T_stop procedure and the CGCD method have indicated that peak 6 has general-order kinetics too. The activation energy found with the IR, VHR, PS and CGCD methods for peak 4 yield very close values. For all other peaks, there is no agreement between the results of all the applied methods. This work also indicates that the post-irradiation annealing and the heating rate have pronounced effects on the evaluated kinetic parameters of all glow peaks.