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Abstract: MTS-N detectors are pellets of LiF:Mg,Ti produced at the Institute of Nuclear Physics (IFJ) in Krakow, Poland. The thermoluminescence (TL) response of these detectors to gamma radiation doses up to 10 kGy only has been studied earlier. The aim of this paper is to evaluate the TL and EPR response of MTS detectors irradiated with 60Co gamma radiation at high doses up to 1200 kGy. The results indicate that the MTS-N glow curve presents a new peak at temperature near 420 °C for doses over 700 kGy. This peak is probably associated with the second EPR signal that appears for doses over 100 kGy. The defect center related to this signal is undergoing further studies. [Copyright &y& Elsevier]

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 CaSO 4 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. CaSO 4 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. • The dependence on the temperature is different between the two protocols. • The high temperature peaks of the LiF samples follow strong competition effects. • Peak 5 of LiF and peak 2 of BeO do not follow strong competition effects. • The LiF samples can be categorized in two groups. • CaSO 4 samples show no increase in intensity through the thermal treatment. [ABSTRACT FROM AUTHOR]