Effect of pre-irradiation annealing treatments on the response of high-temperature glow peaks of LiF:Mg,Ti

A need to study the effect of pre-irradiation annealing on LiF:Mg,Ti was recognized to enhance the intensity of its high-temperature thermoluminescence (HTTL), and the ratio of HTTL and dosimetric glow peaks (DP). Slow cooling following thermal annealing enhanced the intensity of HTTL and reduced the DP. Following 400 °C - 1 h annealing (established for this type of phosphor and used widely), additional pre-irradiation annealing treatments and oven-cooling (by switching off the power to the oven) were investigated in steps of 20 °C in the range of pre-set temperatures from 400 °C to 100 °C. The oven-cooling from pre-set temperature of ∼170 °C enhanced the HTTL and the HTTL/DP ratio by up to 1.66 and 4.88 times, respectively, as compared to that for the fast cooling from 400 °C but reduced the DP by 2.9 times. The slow cooling from pre-set temperatures in the range of 180 °C-160 °C appears crucial for the intensities of DP and HTTL, and thereby for the applicability of LiF:Mg,Ti in mixed-field dosimetry of low and high LET radiation.