Abstract: In this study, two kinds of LiF(Mg,Cu,P)thermoluminescence detector, namely the TLD-2007C and TLD-SWB TLDs, were irradiated in standard Gamma radiation field. The uniformity, repeatability and linearity of the response to γ rays were compared in order to ensure the measurements accuracy. The variation coefficient of their sensitivities under different absorbed doses were analyzed and the linear upper limit was obtained. The results indicated that the reading coefficient of variation of TLD-2007C and TLD-SWB was 3.5% and 3.2% respectively when the absorbed dose was 10 mGy,and the repeatability indicator was within 5%. The linear response upper limits of TLD-2007C and TLD-SWB were between 12 to 15 Gy and 10 to 12 Gy respectively. The sensitivity of TLDs changed little when reusing with radiation below the upper limit, but decreased for the radiation beyond the upper limit. If reused in radiation filed beyond the upper limit, the sensitivity of the TLD-2007C could maintain the new decreased level, while the sensitivity of the TLD-SWB continued decreasing. Completed integrated annealing cycle was necessary in order to recover its sensitivity. The results also indicated that the uniformity of the group of TLDs with consistency screening could remain well no matter their absorbed dose were beyond the upper limit.

Key words: LiF(Mg,Cu,P)thermoluminescence detector, TLD-SWB, uniformity, linearity, repeatability