O^(2+)离子穿过碳膜引起的前后表面电子发射  

Forward and Backward Secondary Electron Emission from Carbon Foils by O^(2+) Ion

作　　者：虞洋[1,2] 赵永涛[1] 王瑜玉[1] 王兴[1] 程锐[1] 周贤明[1] 李永峰[1,2] 刘世东[1,2] 雷瑜[1] 孙渊博[1] 

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]中国科学院大学,北京100049

出　　处：《原子核物理评论》2014年第1期92-95,共4页Nuclear Physics Review

基　　金：国家重点基础研究发展计划项目(973计划)(2010CB832902);国家自然科学基金资助项目(11075192;11105192;11275241;11275238;11205225)~~

摘　　要：测量了入射能为1.9~11.3 keV/u的O^(2+)离子穿过碳膜诱导的前向、后向(分别对应出射表面和入射表面)电子发射产额。实验中,通过改变入射离子的能量和流强,系统地研究了电子能损和离子束流强度对前向、后向电子发射产额的影响。结果表明,在本实验的能量范围内,前向、后向电子发射产额与对应表面的电子能损有近似的正比关系,而与束流强度无关。分析还发现引起后向电子发射的动能阈值约为0.2 keV/u,势能电子发射产额约为1 e^-/ion。We have measured the secondary electron emission yields in forward and backward directions from the carbon foils, which are penetrated by 02＋ ion of the energy form 1.9 to 11.3 keV/u. In the experiment, the role of electronic energy loss and ion beam intensity in forward and backward electron emission yields have been systematically studied by changing the projectile ion energy and ion beam intensity. The results show that~ forward and backward electron emission yields are approximately proportional to the electron energy loss at the exit surfaces and entrance surfaces respectively, and they are independent of the ion beam intensity. Further analyses show that, the kinetic energy threshold for the backward electron emission is about 0.2 keV/u, where the electron emission yield due to the potential energy deposition was roughly 1 e-/ion in the experiment.

关 键 词：电子发射 电子能损 离子束流强度 

分 类 号：O571.33[理学—粒子物理与原子核物理]