加速器束流脉冲化及氢二次离子发射研究  

Application of HTS in Pulsed Ion Beam of Sccelerator and Study on Secondary Ion Emission of Hydrogen from Carbon Nanotubes under Bombardments of MeV Si and Si_2 Clusters

作　　者：丁富荣[1] 史平[1] 王尧[1] 聂锐[1] 沈定予[1] 马宏骥[1] 

机构地区：[1]北京大学技术物理系,北京100871

出　　处：《原子核物理评论》2004年第1期34-37,共4页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(10175005);北京大学重离子物理研究所分析资金资助~~

摘　　要：详细介绍了快速高压晶体管开关在加速器束流脉冲化和用于二次离子测量的加速器飞行时间谱仪上的应用.利用飞行时间法研究了碳纳米管在不同能量的Si和Si2团簇离子轰击下氢二次离子的发射.实验结果表明,在每个原子质量单位的速度为2.5×108cm/s以上,Si和Si2离子引起的氢二次离子的发射主要受电子阻止过程控制;在每个原子质量单位的速度为2.5×108cm/s以下和Si2团簇离子轰击的情况下,氢二次离子的发射产额明显增加,团簇离子在靶表面的核能损增强效应起主要作用.The application of Fast High Voltage Transistor Switches (HTS) in pulsed ion beam and the time of flight(TOF ) setup is described. Secondary ion emissions from carbon nanotubes under bombardments of MeV Si and Si_(2) clusters are measured by using TOF. The measurements indicate that the yield of the secondary ion emissions of hydrogen increases with increasing energy of Si and it is attributed to the (electronic) processes. The yield of the secondary ions of hydrogen decreases with increasing energy of Si_(2) clusters and the enhancement of nuclear energy loss of cluster constituents at the surface of sample plays a more significant role in the secondary ion emission of hydrogen at the low energies.

关 键 词：加速器 飞行时间 团簇离子 二次离子发射 阻止本领 束流脉冲化 核能损增强效应 

分 类 号：TL817.8[核科学技术—核技术及应用] O571.33[理学—粒子物理与原子核物理]