Proton Induced X-ray Emission
Non-destructive, Simultaneous Analysis for 72 Inorganic Elements from Sodium through Uranium
Proton Induced X-Ray Emission (PIXE) is a method for the determination of the elemental composition of a sample. This method is based on the emission of characteristic x-rays by the target elements following irradiation with a proton. The X-ray spectrum is initiated by energetic protons exciting the inner shell electrons in the target atoms, leaving vacancies in the inner shell, and X-rays are generated when the created vacancies are filled. Since the X-rays are characteristic of the elements from which they originate and there is little overlapping of the characteristic x-rays for different elements, simultaneous detection of complicated multi-elements sample is possible.
PIXE has the following advantages:
- High Sensitivity (detection limit ~1 ppm for thin foils and ~10 ppm for thick samples)
- Measurement at Atmospheric Pressure Possible (by allowing the beam to exit from the beam line through a thin window, large samples may be analyzed in air).
- Multi-element Capability (major elemental analysis is performed for any element from sodium to uranium in a single spectrum )
- Non-destructive (minimal beam induced effects on the specimen)
- Surface sensitive method (typical analysis depth is on the order of 1 µm)