On the linearity of the high temperature peaks of LiF:Mg,Ti

LiF:Mg,Ti has glow peaks also at temperatures higher than the main dosimetry peaks, which have a different LET sensitivity. Works in the past dealt mostly with high irradiation doses, and a supralinear response of peak 7 to gamma-rays was reported, making the applicability of the peak ratio method for neutron-gamma discrimination questionable. In the present work, the region of interest (ROI) method was applied for determining the contributions in the various regions of the glow curve, after thermal neutron and gamma ray irradiation in the range of doses common to personal dosimetry (up to about 50 mSv). It was found that the area of the ROI of peaks 6+7 is linear with dose for thermal neutrons and gamma rays, as also the area of peaks 4+5. Because the ratio between those areas is also constant for either thermal neutrons or gamma rays, but significantly different for the two radiations (about one order of magnitude), it seems that the use of the high temperature peaks in LiF:Mg,Ti for neutron and gamma dose evaluation in mixed fields is feasible, at least for the dose levels expected in practical radiation protection. (c) 2004 Elsevier Ltd. All rights reserved.