RBS法测量重元素衬底上轻元素薄靶厚度的方法研究  

Thickness Measurement of Light Element Thin Target on Heavy Element Substrate with RBS Method

作　　者：吴笛 仇猛淋 王乃彦 郭冰[1] 贺创业[1] 王广甫[2] 樊启文[1] 党永乐[1,2] 刘伏龙 付光永 杨婉莎 魏继红 WU Di;QIU Menglin;WANG Naiyan;GUO Bing;HE Chuangye;WANG Guangfu;FAN Qiwen;DANG Yongle;LIU Fulong;FU Guangyong;YANG Wansha;WEI Jihong(Department of Nuclear Physics,China Institute of Atomic Energy,Beijing 102413,China;Key Laboratory of Beam Technology of Ministry of Education,College of Nuclear Science and Technology,Beijing Normal University,Beijing 100875,China)

机构地区：[1]中国原子能科学研究院核物理研究所,北京102413 [2]北京师范大学核科学与技术学院射线束技术教育部重点实验室,北京100875

出　　处：《原子能科学技术》2021年第2期348-352,共5页Atomic Energy Science and Technology

基　　金：国家自然科学基金资助项目(11975316,11490560);国家重点研发计划资助项目(2016YFA0400502);国家财政部稳定支持研究经费资助项目(WDJC-2019-02)。

摘　　要：在核反应实验中,靶厚的精度往往会直接影响实验结果的可靠性。为精确测量重元素衬底上轻元素薄靶的厚度,本文通过卢瑟福背散射(RBS)法,使用能量1.5 MeV的质子束对蒸镀在300μm厚181 Ta衬底上薄74 Ge靶的厚度进行了测量。RBS法测量结果与称重法相差较小,但信噪比从1∶2000提升到1∶12,靶厚相对不确定度由10%减少到5%左右。同时采用SIMNRA软件对测量结果进行了模拟验证,模拟能谱与实验能谱符合较好。通过RBS法测量重元素衬底上轻元素薄靶的厚度,尤其当重元素衬底的质量远大于靶物质时,可有效提高测量结果的信噪比及不确定度,为核反应实验的分析提供了较好的依据。The accuracy of target thickness has a great influence on the reliability of the result in nuclear reaction experiment.In order to measure the thickness of light element thin target on the heavy element substrate,a 1.5 MeV proton beam was used to measure a thin 74 Ge target evaporated on a 181 Ta substrate which has a thickness of 300μm with Rutherford backscattering(RBS)method.The difference of measurement result between RBS method and weighing method is small,but the signal-noise-ratio increases from 1∶2000 to 1∶12 and the thickness relative uncertainty decreases from 10%to about 5%compared with weighing method.SIMNRA simulation was also performed to check the measurement result,which matches well with experiment energy spectrum.RBS method can effectively improve the signal-noise-ratio and uncertainty when measuring the thickness of light element thin target on a heavy element substrate,especially when the substrate is much heavier than the target,which provides a good basis for the data analysis in nuclear reaction experiment.

关 键 词：卢瑟福背散射 薄靶 厚度 金硅面垒探测器 

分 类 号：TL814[核科学技术—核技术及应用]