An improvement of the new method for evaluating the paleodose

Abstract

A new method of evaluating the pareodose, the auther presented in 1988, extended the limits of the TL dating method to about 10⁶ years.
In the former article, consideration about the electron-trapping process produced the combination of a competition model and an ordinary saturation model. The competition model accounts for the supralinearity in the low dose range, and the ordinary saturation model explains the sublinearity in the high dose range. In the new method, the experimental data decide the coefficients of the equation directly, without the regressive error. Therefore, in many types of samples, the new method brought good results for evaluation of the pareodose.
In some cases, however, a few errors have appeared in the low dose range. In the former article, the electron-trapping probability of the competition model was doubly approximated, in order to make a solution easy. The double approximation caused a few errors in the calculation of TL responce, in the low dose range, Consequently, the former equation led a smaller value as a pareodose.
For the purpose of a solution, the approximate term of (1-e7^-CR) was exchanged for the correct term of (1+e^-CR+D)-1. The improved equation has offered better-fitting results with experiments, especially in the low dose range.
By this improvement, the new method has enhanced the reliability and has come to be of wide application.