Reappraisal of Peak Shape Method Based on Average Geometrical Symmetry Factor and Its Application to Thermoluminescence Glow Curves

Abstract

A new set of peak shape formulas at different fractional intensities is proposed to extract the activation energy from a thermoluminescence (TL) glow curve. The peak shape coefficients are formulated on the basis of the average geometrical symmetry factor which is estimated considering its dependence on the relevant TL parameters. An empirical dependence of the geometrical symmetry factor on order of kinetics and other parameters is also reported. The present method is used on TL peaks generated in general order kinetics (GOK) approximation and in one trap one recombination center (OTOR) model using a wide range of TL parameters. During the course of TL peak simulation, an alternative analytical approach to evaluate the “temperature integral” is developed. The present method seems to be useful to evaluate the activation energy for all peaks except for the heavy retrapping cases when the initial trap saturation is considerably high. A probable reason behind this limitation is also explored by examining the correspondence between the temperature average of order of kinetics and the retrapping‐to‐recombination probability. Finally, the new peak shape formulas are tried on isolated single peaks deconvoluted from composite experimental TL curves reported in the literature and the results are quite satisfactory.