Application of thermoluminescence (TL), continuous optically stimulated luminescence (COSL) and pulsed optically stimulated (POSL) for mixed field neutron–gamma dosimetry using LiF:Mg,Ti (TLD-700)

Accurate neutron dosimetry is essential in mixed radiation fields due to the high radiobiological effectiveness of neutrons compared to gamma rays. This study investigates the combined use of thermoluminescence (TL), continuous optically stimulated luminescence (COSL), and pulsed OSL (POSL) with ⁷LiF:Mg,Ti (TLD-700) detectors for the separate estimation of the dose deposited by high ionization density (HID) and low ionization density (LID) radiation. TLD-700 samples were irradiated with fast neutrons of a median energy of 6 MeV and gamma and beta radiation. The calibration coefficients for the TL, OSL, and POSL signals were previously measured, and the dose components were determined using coupled linear equations. The results indicate that the combined TL–COSL and TL–POSL methods can estimate neutron and gamma doses with a precision of the order of ±10% (1 SD) and that deviations from “true” values in mixed-field conditions were typically below 10%. The influence of PMMA covers on the luminescence response was negligible in these experiments. Although TLD-700 exhibits low neutron sensitivity, its stable and reproducible luminescence properties enable neutron–gamma discrimination when paired with COSL/POSL. The findings indicate that the proposed method enables reliable estimation of the individual radiation dose components in mixed neutron–gamma radiation fields using TLD-700 detectors.