EFFECTS OF NONIDEAL HEAT-TRANSFER ON THE GLOW CURVE IN THERMOLUMINESCENCE EXPERIMENTS

A model for the heat transfer between a heating element and a thermolu minescent sample in the case of contact heating is used to estimate th e temperature lag of the sample with respect to the heating element du ring linear heating. According to the model the temperature lag is lin early dependent on the heating rate beta and the temperature differenc e between the heating element T1 and the surroundings T(g). For a LiF: Mg, Ti(TLD-100) sample with dimensions 3.2 x 3.2 x 0.9 mm3 the tempera ture lag DELTAT during linear heating can be described by DELTAT = 1.7 beta + 0.037(T1 - T(g)). Compared to DELTAT the temperature gradient a cross the TLD-100 sample can be neglected. The consequences of neglect ing phenomena such as temperature lag and gradient, which always occur to some extent in TL measurements, on trapping parameters (activation energy and frequency factor) derived by glow curve analysis are discu ssed.