目的 研究热释光探测器(TLD)的剂量学特性.方法 选取一致性为±3％的TLD2000型热释光探测器350片.采用6MVX射线和125I粒子分别照射,研究热释光探测器对6MVX射线和125I粒子响应的重复性以及剂量率效应.采用137Cs(662 keV γ射线)、125I粒子、6MVX射线分别照射热释光探测器,研究热释光探测器的剂量响应.采用125I粒子、137Cs和X射线(48、65、83、118、250 keY和6 MV)对热释光探测器照射相同剂量,研究热释光探测器的能量响应.结果 热释光探测器对于6MVX射线和 125I粒子响应重复性最大偏差分别为2.7％和4.0％,且均无剂量率效应.对于137 Cs和125I粒子,热释光探测器的剂量响应均为线性.对于6MVX射线,剂量线性响应范围为0.74 ～ 10 Gy,超过10 Gy热释光剂量响应呈非线性.能量响应按照137Cs进行归一,对于125I粒子,48、65、83、118、250 keV和6 MV能量X射线,能量响应分别为1.70、1.25、1.08、0.99、0.91、0.96和1.22.结论 TLD 2000型热释光探测器的重复性好,对于137 Cs、125I粒子和6MVX射线的剂量响应呈线性,且无剂量率效应,但存在能量响应.%Objective To study the dosimetric characteristics of thermoluminescent dosimeter (TLD).Methods A total of 350 pieces of TLD 2000 type TLDs having the same sensitivity within ± 3.0％ were selected.The TLDs were irradiated to study the repeatability and dosage effect of TLDs by using 6 MV X-rays and 125I seeds.In order to study the dose response,the TLDs were irradiated at different dosages by using 137Cs (662 keV γ-rays),125I seeds and 6 MV X-rays.In order to study the energy response,the TLDs were exposed to the same dose,from 125I seeds,137Cs and X-rays(48,65,83,118,250 keV and 6 MV).Results The maximum deviations of the repeatability were 2.7％ and 4.0％ for 6 MV X-rays and 125I seeds,respectively,and there was no effect of dose rate observed.The dose response of TLDs to 137Cs and 125I seeds were linear.For 6 MV X-rays,the linear response was within the range of 0.74-10 Gy and non-linear range was beyond 10 Gy.The energy response to 125I seeds,48,65,83,118,250 keV and6 MV X-rays,relative to the energy response of 137Cs,were 1.70,1.25,1.08,0.99,0.91,0.96 and 1.22,respectively.Conclusions TLD 2000 has a good repeatability and linear dose response for 137Cs,125I seeds and 6 MV X-rays with no dose rate effects,but the dose response is energy dependent.
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