Ion-Beam Analysis of Airborne Pollution

A research program in ion-beam analysis (IBA) of atmospheric aerosols is being developed to study pollution in the Capital District and Adirondack Mountains of New York. The IBA techniques applied in this project include proton induced X-ray emission (PIXE), proton induced gamma-ray emission (PIGE), Rutherford backscattering (RBS), and proton elastic scattering anal-ysis (PESA). These methods are well suited for studying air pollution because they are quick, non-destructive, require little to no sample preparation, and capable of investigating microscopic samples. While PIXE spectrometry is used to analyze most elements from silicon to uranium, the remaining techniques an-alyze some of the lighter elements to complement PIXE in the study of aerosols. The airborne particulate matter is collected using nine-stage cascade impactors that separate the particles according to size and the samples are bombarded with proton beams from the Union College 1.1-MV Pelletron Accelerator. The reaction products are measured with Si Drift X-ray, Ge gamma-ray, and Si sur-face barrier charged particle detectors. Here, we report on the progress we have made on the PIGE, RBS, and PESA analysis of aerosol samples