用于中子俘获反应截面测量的康普顿相机读出电子学研究  

Research on the readout electronics of a Compton Camera for Neutron Capture Cross Section Measurement

作　　者：王维宇 曹平[1,3] 孙振宇 任杰[5] 王金成 Wang Weiyu;Cao Ping;Sun Zhenyu;Ren Jie;Wang Jincheng(State Key Laboratory of Particle Detection and Electronics,University of Science and Technology of China,Hefei 230026,China;Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China;School of Nuclear Science and Technology,University of Science and Technology of China,Hefei 230026,China;Institute of Advanced Technology,University of Science and Technology of China,Hefei 230031,China;Key Laboratory of Nuclear Data,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]核探测与核电子学国家重点实验室,中国科学技术大学,安徽合肥230026 [2]中国科学技术大学近代物理系,安徽合肥230026 [3]中国科学技术大学核科学技术学院,安徽合肥230026 [4]中国科学技术大学先进技术研究院,安徽合肥230031 [5]中国原子能科学研究院,核数据重点实验室,北京102413

出　　处：《核电子学与探测技术》2025年第2期145-153,共9页Nuclear Electronics & Detection Technology

基　　金：国家自然科学基金项目(资助编号12075237)。

摘　　要：CSNS Back-n实验环境中复杂的γ本底会影响中子俘获截面测量结果的准确性。本文将康普顿散射成像的原理引入总能量型探测器,开展用于中子俘获反应截面测量的康普顿相机读出电子学的研究,通过计算γ射线的入射方向抑制本底,从而提高效应本底比。其中探测器选用低本底高分辨的CeBr_3晶体耦合硅光电倍增管(SiPM)进行设计,并基于ASIC和FPGA对320路SiPM输出信号进行读出,通过高性能TDC与QDC实现对γ射线的时间与能量的测量。经过测试,康普顿相机的能量分辨率好于5.7%@662 keV,符合时间分辨σ_t为0.66 ns,eV能区和keV能区的效应本底比分别是现有C_6D_6探测器的1.61倍和3.30倍。测试结果说明了该方案的可行性,可为在Back-n上开展中子俘获反应截面测量提供技术支撑。The complexγbackground in the CSNS Back-n experimental environment will affect the accuracy of measurement results.In this thesis,the principle of Compton scattering imaging is introduced into the total energy detectors(TED).In addition,the readout electronics of a Compton camera is studied,which is applied for neutron capture cross section measurements.The Compton camera can be used to enhance the signal-to-background ratio by eliminating irrelevant backgrounds.Within the Compton camera,the detectors are designed utilizing low-background high-resolution CeBr3 scintillation crystals coupled with silicon photomultiplier(SiPMs).Moreover,320 channels of SiPM output signals are read out utilizing ASICs and FPGA.High-performance TDC and QDC are employed for measuring the time and energy ofγ-rays.After testing,the energy resolution of the Compton camera is better than 5.7%@662 keV,and the coincidence time resolution(CTR)σt is 0.66 ns.Additionally,the background-to-signal ratios in the eV and keV energy ranges are 1.61 times and 3.30 times higher than those of existing C6D6 detectors.The test results demonstrate the feasibility of the camera,which offers technical support for experiments such as neutron capture cross section measurements at Back-n.

关 键 词：中子俘获反应截面 CeBr_(3)探测器 康普顿相机 读出电子学 

分 类 号：TL657[核科学技术—核技术及应用]