γ-γ符合测量系统的新型前端读出电路研制  

Development of New Front-end Readout Electronics forγ-γCoincidence Measurement System

作　　者：颜俊伟 牛晓阳[1,2] 柯凌云 杨海波 陈金达[1] 杜成名[1] 张秀玲[1] 孙志朋[1,2] 苏弘 孔洁[1] YAN Junwei;NIU Xiaoyang;KE Lingyun;YANG Haibo;CHEN Jinda;DU Chengming;ZHANG Xiuling;SUN Zhipeng;SU Hong;KONG Jie(Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China;School of Nuclear Science and Technology,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院近代物理研究所,甘肃兰州730000 [2]中国科学院大学核科学与技术学院,北京100049

出　　处：《原子能科学技术》2020年第8期1500-1507,共8页Atomic Energy Science and Technology

基　　金：国家自然科学基金面上项目资助(11775285,11605265);国家重点研发计划资助项目(2016YFB0701001);中科院“青年创新促进会”资助项目(2016362,2019408);中科院区域中心功能开发技术创新资助项目(2020g101);中科院海西创新研究院自主部署资助项目(FJCXY18040201)。

摘　　要：研制了一种新型前端读出电路,用于重离子治癌装置中符合测量原型系统的研究和测试。电路主要包括能量链、时间链和数据处理单元。能量链由截止频率7 MHz的抗混叠滤波器和模数转换器(ADC)组成,形成波形采样电路;时间链由高速比较器构成的定时甄别电路和时间数字转换器(TDC)组成;数据处理单元基于现场可编程门阵列(FPGA)设计实现。电路的线性度优于0.8%,噪声小于0.8 mV(RMS)。配合LaBr 3单晶体条测试,能量分辨为4.5%(FWHM),在与LYSO晶体阵列配合测试时,位置映射散点图清晰。该前端读出电路性能优于CAMAC系统,具有较好的实际应用前景。A new front-end readout electronics was developed,which was used for research and testing of the prototype coincidence measurement system in the heavy-ion cancer therapy device.The circuit mainly includes the energy measurement chain,time measurement chain and data processing unit.The energy measurement chain is composed of an anti-aliasing filter with a cut-off frequency of 7 MHz and an analog-to-digital converter(ADC),which forms a waveform sampling circuit.The time measurement chain is composed of a timing discrimination circuit formed by high-speed comparator and a time-to-digital converter(TDC).The data processing unit is designed and implemented based on a field programmable gate array(FPGA).The linearity of the circuit is better than 0.8%and the noise is less than 0.8 mV(RMS).It was tested coupled with a LaBr 3 crystal strip,and the energy resolution is 4.5%(FWHM).Meanwhile,the test was performed with the LYSO crystal detection array,and the position map scatter plot is clear.The performance of the developed front-end readout circuit is superior to the CAMAC system and has a good practical application prospect.

关 键 词：符合测量系统 前端读出电路 现场可编程门阵列 能量分辨 位置分辨 

分 类 号：TL82[核科学技术—核技术及应用]