Studies of thermoluminescence kinetic parameters of polymer pencil lead graphite under photon exposures

This study analysed thermoluminescence (TL) glow curves of the polymer pencil lead graphite (PPLG) due to its potential applications in radiation dosimetry. The TL glow curves provide information on the physical parameters of the defects participating in luminescence process. The glow curves for different diameters PPLG samples were obtained with varying temperature from 50 to 300 °C, at a fixed heating rate of 10 °Cs^-1. A number of methods (initial rise, peak shape and curve fitting) were used to fit the TL glow peaks of the PPLG samples obtained under photon dose of 200 Gy. From the fitted TL signals, the trap parameters such as the order of kinetics, the activation energy, the frequency factor, etc. for the individual peaks were numerically determined. The lifetimes of TL process were calculated assuming the first-order kinetics. The results are compared among the different methods adopted in this study. Implications about the possible results in glow curve deconvolution are discussed.