Radio-photoluminescence of highly irradiated LiF:Mg,Ti and LiF:Mg,Cu,P detectors

摘要

The radio-photoluminescent (RPL) characteristics of LiF:Mg,Ti (MTS) andLiF:Mg,Cu,P (MCP) thermoluminescent detectors, routinely used in radiationprotection dosimetry, were investigated after irradiation with ultra-highelectron doses ranging up to 1 MGy. The photoluminescence of both types of LiFdetectors was stimulated by a blue light (460 nm) and measured within aspectral window around 530 nm. The RPL dose response was found to be linear upto 50 kGy and sublinear in the range of 50 kGy to 1 MGy for MCP detectors andlinear up to 3 kGy and next sublinear in the range from 5 kGy to 1 MGy for MTSdetectors. For both type of LiF detectors RPL signal is saturated for doseshigher than 100 kGy. The observed differences between MCP and MTS may suggest,that the RPL effect in LiF is not entirely governed by intrinsic defects (F2and F3+ centers), but impurities may also have a significant influence. Due tothe non-destructive character of the RPL measurement, it is suggested to applycombined RPL/TL readouts, what should improve accuracy of high-dose dosimetry.