气溶胶样品氢含量的质子弹性散射分析

Proton Forward Elastic Scattering Analysis for Measuring Hydrogen Concentrations of Aerosol

摘要: 利用单个标准样品比较法质子弹性散射分析（PESA）对一组采集在核孔膜上的气溶胶样品的氢含量进行定量分析。在质子束能量为2.5 MeV、散射角为40°时，PESA测量10 μm 厚核孔膜上气溶胶中H含量的探测限为0.36 μg/cm²。几个样品H含量的测量结果在3.2~37.5 μg/cm²之间，显著高于探测限。质子能量在1.0~2.5 MeV范围内，3.5 μm Mylar膜的束流归一化H峰面积随入射质子能量的变化在±3%以内。所以，不同厚度的气溶胶样品可采用同一个标准样品来进行PESA测量。

Abstract: Proton elastic scattering analysis(PESA) method was employed to measure H concentrations of aerosol samples on nuclear track filter. With 2.5 MeV proton beam and 40 degree scattering angle, the detection limit of PESA is 0.36 μg/cm² for aerosol samples on 10 μm nuclear track filters. The PESA results show that H concentrations of these aerosol samples are from 3.2 to 37.5 μg/cm², much higher than the detection limit of PESA. The measured scattering cross sections of proton from H vary within ±3% in the range of 1.0-2.5 MeV, so a single standard sample can be used for samples with different thicknesses.