Unified theory of gamma and heavy charged particle TL supralinearity: The track/defect interaction model

The unified track/defect interaction model (UNIM) provides the microscopic/geometric framework which, when coupled with other appropriate physical mechanisms (competing centres in the recombination stage, variations in the capture cross section with temperature, etc.), can be used to describe all the dominant features of the TL linear-supralinear behaviour of LiF:Mg,Ti. In this work it is shown how the same mathematical formalism can accurately fit the linear-supralinear dose-response curve of alpha particles as well as gamma rays. In both cases, the primary mechanism leading to TL supralinearity is a decrease in the effectiveness of non-luminescent competitors as the dose increases. This decrease in competition arises because of the decrease in the distances between the occupied trapping centres and the occupied luminescence centres as the dose increases.