便携式γ能谱仪闪烁探头改进设计及性能研究  

Improved Design and Performance Research on Portable γ Spectrometry Scintillation Probe

作　　者：李元东[1] 葛良全[1] 王彦瑜[2] 张开琪 胡传皓 卢威骅 孙坤[1] 黄锐[1] LI Yuan-dong GE Liang-quan WANG Yan-yu ZHANG Kai-qi HU Chuan-hao LU Wei-hua SUN Kun HUANG Rui(Nuclear Technology Key Laboratory of Earth Science in Sichuan , Chengdu University of Technology, Chengdu 610051, China Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China China Institute for Radiation Protection, Taiyuan 030006, China)

机构地区：[1]成都理工大学地学核技术四川省重点实验室,四川成都610051 [2]中国科学院近代物理研究所,甘肃兰州730000 [3]中国辐射防护研究院,山西太原030006

出　　处：《原子能科学技术》2017年第8期1471-1477,共7页Atomic Energy Science and Technology

基　　金：国家自然科学基金资助项目(41474159);四川省科技计划资助项目(2015JQO035);地学核技术四川省重点实验室开放基金资助项目(gnzds2014006)

摘　　要：为满足当前便携式γ能谱仪对高性能闪烁探头的需要,本文提出了采用CsI(Tl)晶体耦合雪崩光电二极管的方式代替NaI(Tl)晶体耦合光电倍增管以构成新的闪烁探测器,并设计了低噪声电荷灵敏放大器作为探测器读出电路。根据唯一变量原则分别测试了能量分辨率随温度与偏压的变化规律,并对多种放射源的γ射线进行能谱响应实验。实验结果表明:当温度为23℃且偏压为370V时,该闪烁探头对^(137) Cs、^(226) Ra、^(60) Co和^(152) Eu源的γ射线具备优异的能谱响应特性,其中,对^(137) Cs源的γ射线能量分辨率可达4.98%,输出信号信噪比可达21∶1,上升时间为80ns。可见,改进后的闪烁探头的性能有大幅提升,具备能量分辨率更佳、体积更小、抗机械性能与适用性更强等优点。In order to fill the need of high-performance scintillation probe for the current portableγspectrometry,the CsI（Tl）crystal coupled with avalanche photo diode was adopted to constitute a new scintillation detector instead of NaI（Tl）crystal coupled with photomultiplier,also a low-noise charge sensitive amplifier was designed to serve as a readout circuit for the detector.For researching the performance of the improved scintillation probe,the regularity of the energy resolution changing with the temperature and the bias voltage was tested respectively based on the unique variable principle and experiments with spectrum response ofγray for various radiation sources.The results showthat the scintillation probe has a excellent characteristic of spectrum response for ^（137） Cs,^（226） Ra,^（60） Co and ^（152） Eu sources when the temperature is 23 ℃ and the bias voltage is 370 V.Especially,the energy resolution is 4.98%,the SNR of the output signal is 21∶1 and the rise time is 80 ns for ^（137） Cs.Thus it can be seen that the improved scintillation probe,which has better energy resolution,smaller size and stronger performance of anti-mechanical and applicability,is significantly more excellent than the conventional one.

关 键 词：Γ能谱仪 闪烁探头 电荷灵敏放大器 雪崩光电二极管 能谱响应 能量分辨率 

分 类 号：TL812.1[核科学技术—核技术及应用] TL821