用于聚变装置的溴化镧探测器在0.1~11 MeVγ能区的能量刻度和效率刻度研究  

Study of the energy calibration and efficiency calibration of a lanthanum bromide detector for fusion devices in the 0.1~11 MeVγenergy region

作　　者：叶茜 罗小兵[1] 祝家俊 鄢文轩 罗冬梅[1] YE Xi;LUO Xiao-Bing;ZHU Jia-Jun;YAN Wen-Xuan;LUO Dong-Mei(Key Laboratory of Radiation Physics and Technology,Ministry of Education,Institute of Nuclear Science and Technology,Sichuan University,Chengdu 610064,China)

机构地区：[1]四川大学原子核科学技术研究所辐射物理及技术教育部重点实验室,成都610064

出　　处：《四川大学学报(自然科学版)》2025年第2期451-457,共7页Journal of Sichuan University(Natural Science Edition)

基　　金：国家磁约束核聚变能发展研究专项(2019YFE03010003)。

摘　　要：托克马克约束等离子体在破裂期间,会产生高能硬X射线,对这些高能硬X射线的探测有助于理解聚变装置中约束等离子体破裂变化情况.针对核工业西南物理研究院中国环流三号(HL-3)装置上对高能量硬X射线诊断的需求,本文开展了溴化镧探测系统的研制工作.研制的溴化镧探测器系统晶体尺寸为φ76 mm×76 mm,对研制的溴化镧探测器进行了性能测试:该探测器在屏蔽体中本底计数率为455 cps;采用标准源^(137)Cs测量得到的对662 keVγ射线的能量分辨率为3%;采用标准源^(137)Cs、^(152)Eu进行了2 MeV以下γ能区的能量刻度和全能峰探测效率刻度工作;2 MeV以上γ能区,由于缺乏标准γ源,因此采用热中子活化^(14)N等轻元素产生的2~11 MeV能区的高能量γ射线,完成了在该能区的能量刻度和效率刻度.实验结果表明:研制的溴化镧探测器在0.1~11 MeVγ能区有良好的能量线性,标准源刻度得到的全能峰探测效率典型误差小于1.89%.采用MCNP5对研制的溴化镧探测器的全能峰探测效率进行了模拟计算,并与实验测量结果进行了对比分析.Tokomak confinement plasma generates high-energy hard X-rays during plasma discruption events.Detection of these high-energy hard X-rays provides critical insights into confinement dynamics during breakdown in fusion devices.We have developed a lanthanum bromide detector system to meet the requirements for high-energy hard X-rays diagnostics in the HL-3 device at the Southwest Institute of Physics of the Nuclear Industry.The crystal size of the developed lanthanum bromide detector system isφ76 mm×76 mm,and the performance test of the developed lanthanum bromide detector was carried out:The background count rate of the detector in the shield composed of lead,cadmium,and copper plexiglass is 455 cps,and the 32 keV and 788 keVγ-rays emitted by decaying radionuclides 138La and 40K decayingγ-rays contained in the crystal of lanthanum bromide and the photomultiplier material were analyzed.1461 keVγ-rays from the 40K decay contained in the tube material,and the alpha decay of the naturally occurring radioactive element 227Ac and its daughter contained in the lanthanum bromide crystals also contribute to the background energy spectrum;The energy resolution of 662 keVγ-rays obtained by using the standard source ^(137)Cs is about 3%;The energy calibration of the gamma energy region below 2 MeV has been carried out by using the standard sources ^(137)Cs and ^(152)Eu.The energy calibration and the efficiency calibration of full energy peak detection were carried out in the gamma energy region below 2 MeV;In theγ-energy region above 2 MeV,due to the lack of standard gamma sources,high energyγ-rays produced by thermal neutron activation of light elements such as ^(14)N in the 2~11 MeV energy region were used to complete the energy calibration and the efficiency calibration in this energy region.The neutron source used in the experiments was the Am-Be neutron source with an average energy of 4.5 MeV of emitted neutrons,paraffin wax was used as the neutron moderator,and urea(CH4N2O)with a high nitrogen content was used a

关 键 词：溴化镧探测器 效率刻度 能量刻度 蒙特卡罗 

分 类 号：TL812[核科学技术—核技术及应用]