应用屏栅电离室测量^(16)O(n,α)^(13)C反应的模拟研究  

A Simulation Method for Measurement of the^(16)O(n,α)^(13)C Reaction Using Gridded Ionization Chamber

作　　者：夏聪 胡益伟 刘杰 邬泽鹏 白浩帆 任文凯 陈金象 张国辉[1] XIA Cong;HU Yiwei;LIU Jie;WU Zepeng;BAI Haofan;REN Wenkai;CHEN Jinxiang;ZHANG Guohui(School of Physics,Peking University,Beijing 100871,China;Northwest Institute of Nuclear Technology,Xi’an 710024,China)

机构地区：[1]北京大学物理学院,北京100871 [2]西北核技术研究所,西安710024

出　　处：《现代应用物理》2024年第2期52-60,76,共10页Modern Applied Physics

基　　金：国家自然科学基金资助项目(12075008);核数据重点实验室基金资助项目(6142A08200103)。

摘　　要：基于Geant4建立了一套利用屏栅电离室测量^(16)O(n,α)^(13)C反应的模拟方法,能预测不同入射中子能量、不同屏栅电离室结构、不同工作气体和样品参数等实验条件下屏栅电离室测量到的阴极-阳极幅度2维谱。为了验证该模拟方法的可靠性,在北京大学4.5 MV静电加速器上开展了实验,实验所用的中子能量为5.06 MeV,工作气体为0.3 MPa的Ar与体积分数为3.45%CO 2组成的混合气体(其中的氧作为待测样品)。实验测得了屏栅电离室的阴极阳极幅度2维谱,且模拟与实验结果吻合较好。基于此模拟方法提出了一套实验条件的优化方案,可为下一步在宽能区精确测量^(16)O(n,α)^(13)C反应截面提供参考。A simulation method for measuring the^(16)O(n,α)^(13)C reaction using gridded ionization chamber is developed based on Geant4.The measured cathode-anode two-dimensional spectrum of the gridded ionization chamber could be predicted using the simulation method under different experimental conditions,such as incident neutron energy,structure of the gridded ionization chamber,working gas,and sample parameters.To verify the reliability of the simulation method,experiments were conducted on the 4.5 MV Van de Graff accelerator at Peking University(PKU).The experimental cathode-anode two-dimensional spectrum under 5.06 MeV neutrons with the working gas of 0.3 MPa Ar+3.45%CO 2 is compared with the simulated spectrum,showing a good agreement.Based on the simulation method,an optimization solution for experimental conditions is proposed,which laid a foundation of making accurate measurements of the^(16)O(n,α)^(13)C reaction in a wider neutron energy range.

关 键 词：^(16)O(n α)^(13)C反应 GEANT4 屏栅电离室 阴极阳极幅度2维谱 截面测量 

分 类 号：TL81[核科学技术—核技术及应用] O571[理学—粒子物理与原子核物理]