北京师范大学外束PIXE分析装置的建立

A SETUP FOR EXTERNAL BEAM PIXE IN BEIJING NORMAL UNIVERSITY

北京师范大学串列实验室建立了外束质子激发X荧光(PIXE)分析装置.外束引出窗口采用7.5μm厚Kapton膜.为了保护加速器系统,在外束管道中安装自己设计制作的快速真空保护阀.考虑到绝缘样品不能直接测量束流积分,在RBS靶室放置175nm金箔,并建立了金RBS峰面积和束流积分之间的关系,这样在采集外束PIXE能谱的同时,通过记录金箔RBS信号就可获得束流积分.对GBW07306水系沉积物有证标准物质进行了外束PIXE测量及定性分析,并与真空PIXE结果进行了比较.

An external beam PIXE facility is set up at the tandetron accelerator lab of Beijing Normal University. A 7. 5μm thick Kapton film is used to seal the vacuum of the accelerator pipe. A vacuum safety valve is mounted near the end of the beam line for protecting the tandetron accelerator from the exit window accidental broken. To determine quantity of incident protons, an Au （Si） surface barrier detector is used to measure the RBS Au peak area of the 175 nm Au foil in the RBS chamber. The external PIXE spectrum of the GBW07306 sample is acquired and compared with the vacuum PIXE.