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

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.