Thermoluminescence response of various dosimeters as a function of irradiation temperature

Abstract

The behavior of various TL dosimeters following two different thermal treatments with temperature ranging between 50 and 230 °C, was investigated in this particular study. The thermal treatment consists of two different protocols, including a simultaneous irradiation-heating and a post irradiation heating. The dosimeters that are the subject of the present study include two different families of lithium fluorides, namely the Harhsaw LiF family (TLD-600, TLD-700), LiF of the Krakow university (MTS-600, MTS-700), BeO and the commonly used CaSO4 samples with two different impurities (Dy and Tm). According to the analysis, it seems that the TLDs and MTS-600 are identical with regard to their characteristics, while MTS-700 is different. The treatment showed that the intensities of peak 5 of all LiF samples increases up to 20–30% at 110 °C which is followed by a decrease, while the high temperature peaks of LiF showed a high dependence on the treatment temperatures. As for the case of BeO, one peak has a minor increase of 10% at 80–90 °C and a decrease up to 230%, while the other is stable. CaSO4 samples show no increase and there is a decrease starting at 150 °C. Also, this work studied the kinetic parameters of all peaks for these samples via the computerized glow curve deconvolution method. In the end, there is a categorization of the LiF samples based on their properties and their glow curves. Lastly, the results indicate that the lack of strong increase of the TL response with increasing irradiation temperature for the majority of the TL peaks of these aforementioned phosphors does not support strong competition effects. A notable exception is observed for the high temperature TL peaks in all LiF samples regardless of whether these were purchased from Harshaw or from Poland.