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  • 1 Texas A&M University Center for Trace Characterization, Department of Chemistry 77843 College Station TX USA
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Abstract  

Various ion beam techniques (E≥1 MeV/amu) are compared from the standpoint of their analytical capabilities: Charged Particle Activation Analysis (CPAA), Particle Induced X-Ray Emission (PIXE), Ion Induced γ-Ray Emission for bulk analysis, Prompt Reaction Analysis (PRA), Rutherford Backscattering Spectrometry for surface layer characterization and ion absorptiometry for microscopic analysis. With CPAA and PIXE≥70 elements can be detected with sub-ppm sensitivity. The scope of CPAA is being extended with heavy ion beams for radioactivation of H, He, Li, Be, B, C isotopes. In surface layer characterization recent developments in PRA and RBS also involve heavy ion beams. In RBS they can significantly enhance mass resolution for M>50 in comparison with α scattering. For example,63Cu and65Cu can be quantitatively identified in surface films using a 1 MeV/amu40Ar beam. In microscopic analysis, the nuclear microprobe can provide atom-specific signals from quantities ≥10−12 g on spots of a diameter ≥2 μm. Ion absorptiometry techniques can sense density variations as low as ±0.5% in 1 μm3 or less of sample volume.