低能正电子致厚靶特征X射线产额的初步实验研究  

Preliminary study on characteristic X-ray yields of the thick-targe impacted by low-energy positron

作　　者：田丽霞 房冰冰[2] 杭仲斌 曹兴忠[3] TIAN Lixia;FANG Bingbing;HANG Zhongbin;CAO Xingzhong(School of Nuclear Science and Engineering,East China University of Technology,Nanchang 330013,China;The Engineering&Technical College of Chengdu University of Technology,Leshan 614000,China;Multi-discipline Research Center,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]东华理工大学核科学与工程学院,南昌330013 [2]成都理工大学工程技术学院,乐山614000 [3]中国科学院高能物理研究所多学科研究中心,北京100049

出　　处：《核技术》2021年第1期77-82,共6页Nuclear Techniques

基　　金：国家自然科学基金项目(No.12075056、No.11505028)资助。

摘　　要：通过10~30 keV的正电子轰击纯厚T(i Z=22)靶,采用超薄灵敏层的Si-PIN探测器收集其产生的X射线,通过HPGe探测器收集正电子在靶中湮没产生的511 keV的γ光子计数来计算正电子束流强度,对正电子碰撞厚Ti靶的K壳层特征X射线产额进行了初步测量,并将所得实验数据与基于DWBA(Distorted-Wave Born Approximation)理论的Monte Carlo程序PENELOPE模拟值进行了比较,在所考察的能区范围内两者形状较为一致,但实验值均明显低于理论模拟值,在低能端(≦15 keV)更为显著,从而为今后开展这方面的工作提供了参考。[Background]X-ray emission from solid samples exposed to positron beams in the low-energy region is the basis of some material analysis techniques.[Purpose]This study aims to measure the K-shell characteristic X-ray yields of Ti(Z=22)target collided by 10~30 keV positrons preliminarily.[Methods]Based on the thick-target method,the Si-PIN detector with ultra-thin sensitive layer was adopted to detect the X-rays,and the positron intensity was determined through the 511 keVγphoton counts detected by the HPGe detector.The experimental data were compared with the PENELOPE simulations software which was based on the Distorted-Wave Born Approximation(DWBA)theory.[Results]The results indicate that the shape of the characteristic X-ray yield curves is consistent in the considered energy regions,but the experimental data are obviously lower than those of the simulation,especially in the lower energy(≦15 keV).[Conclusions]The experimental method adopted in this paper is applicable,providing a reference for the future work.

关 键 词：正电子 特征X射线产额 厚靶 PENELOPE模拟 

分 类 号：TL81[核科学技术—核技术及应用]