CHARACTERIZATION OF A NEW PREPARED Li2B4O7: Mn DOSIMETER FOR γ- IRRADIATION HIGH-DOSE DOSIMETRY

A lithium borate thermoluminescence dosimeter with 0.3 wt% of manganese impurity concentration was prepared for high dose levels in the range of 1-30 kGy for gamma irradiation applications. The TLD reader was used for read out purposes from ambient temperature to about 400°C with a heating rate of 6°C/sec. The pre- and post- irradiation anneal temperature was 300°C for 1.5 and 1 hours respectively. The effects of absorbed dose, dose rate, storage time, as well as the temperature and humidity versus pre- and post-irradiation storage time have been studied. The main glow peak was found to occur at 375°C, and the dosimeter response in the range of 1-30 kGy was linear. No significant fading effect of the dosimetric peak was observed after 8 weeks of storage, and the effects of ambient temperature and humidity were less than ±5% at 95% confidence level.