Comparison of responses to γ rays among 4 types of LiF(Mg, Ti)-M thermoluminescence dosimestries

LiF(Mg, Ti)-M thermoluminescence dosimestries(TLDs) are studied and their uniformity, repeatability and linearity of the response to rays are compared. The mean and standard deviation of their readout values are measured. The variable coefficients of their sensitivities under different absorbed doses are analyzed and the influence of the irradiation of high dose beyond linearity upper limit on linearity is obtained. The results indicate that the LiF(Mg, Ti)-M TLD produced by Beijing Research Institute of Chemical Defence exhibits the best performance. For the samples of this type of TLD whose absorbed dose is 6 Gy(Si), the variable coefficient of their readout values is 3.11% and the repeatability indicator is within 5%. The linearity upper limit of this type of TLD is within 50~100 Gy(Si). The drifting of the sensitivity of this type of TLD after exposure to 150 Gy(Si) and annealing is about 11%.