EFFECTS OF ANNEALING ON GLOW PEAK PARAMETERS OF LIF-MG,TI (TLD-100) DOSIMETRY MATERIAL

Computerised glow curve analysis has been used to examine the dependen ce of the peak parameters of LiF:Mg,Ti (TLD-100) on the pre-irradiatio n annealing procedure in the temperature range 353 K to 673 K. The int ensities of the main peaks 1, 2, 3, 4 and 5 as well as the activation energies and frequency factors were found to vary strongly with the pr e-irradiation low temperature annealing. The trends in the changes of the glow curves with respect to peaks 2 and 5 could be explained by th e defect reaction equation MgV reversible arrow (MgV)(2) reversible ar row (MgV)(3) reversible arrow precipitates, and an additional assumpti on that the traps responsible for peak 2 react during read out with Mg V and (MgV)(2). The 'precipitation' process was found to be frozen in at temperatures lower than 373 K. The influences of variations in the cooling rate in the annealing procedure on the glow curve shape are di scussed. It was found that for accurate dosimetry the cooling applied in the annealing procedure is not a very critical factor for high cool ing rates (>1 K.s(-1)) but may be a very critical factor for low cooli ng rates (<0.08 K.s(-1)).