On fading corrections for LiF:Mg,Ti irradiated by thermal neutrons.

The phenomena of preirradiation and postirradiation fading of LiF:Mg,Ti phosphors are considered a significant practical problem in routine dosimetry because of the uncertainties introduced, especially for mixed neutron-gamma dosimetry, as different fading corrections may be necessary for the gamma and neutron contributions. We have investigated if the region of interest (ROI) method is applicable to minimizing the fading effect for thermal neutron irradiation as it is for gamma irradiation. By employing the ROI method, which consists of integration between channel 31 below the glow curve maximum and channel 16 above the glow curve maximum, a constant dose value was obtained for the period of 90 d. Thus, by employing the ROI method, a fading independent evaluation of the thermal neutron dose can be made.