A kinetic model of the rapidly bleaching peak in quartz thermoluminescence

Data manipulation techniques for obtaining a precise estimate of the shape of thermoluminescent (TL) glow curves of the rapidly bleaching peak(RBP, traditionally at 325 degrees C) in quartz are given. A kinetic model for the REP glow curves and glow growth curves applicable to many samples of quartz is then presented. The model contains a single type of high-temperature electron trap (the REP trap), with retrapping, a single type of recombination/luminescence center, row-temperature traps sharing the same recombination center, and deep isolated traps. Optical re-excitation of the trapped REP electrons by the luminescence is included. For the glow curve calculation the latter two features, the low-temperature peaks and the re-excitation of the trapped electrons, do not play a significant role, but they are important for the glow growth curves, where the prompt luminescence is involved. All major kinetic parameters but two are derived from other work. The remaining two parameters, the probability of capture of a conduction electron by a recombination/luminescence center and the concentration of the deep traps, are coupled. With a given value of deep trap concentration a lower limit to the recombination probability can be evaluated by fitting the theoretical glow curve to experimental data. The REP behaves as a first-order peak somewhat distorted in shape by thermal quenching. In the absence of deep traps the model is shown to exhibit radiation quenching. (C) 1998 Elsevier Science Ltd. All rights reserved.