Particle-induced X-ray emission

The abbreviation stands for PIXE particle -induced X-ray emission and proton -induced X-ray emission (Particle Induced X -ray Emission Proton Induced X -ray or emission), and is a common method of ion beam analysis.

The sample is examined in the PIXE with an ion beam. When passing through the sample, the ions lose mainly by interaction with the electron shell energy. It also comes to collisions of the particles with electrons of the inner shells. Thus, these are knocked out of the atomic shell and it comes in the sequence, there may be a de-excitation of the core by characteristic X-rays. This is used in the PIXE for determining the elemental concentration.

The method itself is suitable for heavy elements ( atomic numbers Z > 12 ... 20) and in comparison to other X-ray methods, a significantly lower bremsstrahlung background. This also makes it possible to analyze trace elements.

For light elements of the competing Auger effect the characteristic X-ray emission decreases strongly. In addition, light nuclei emit low-energy X-rays. This is relatively strongly attenuated before the detector through films, which are used among other things for the absorption of the backscattered ions and therefore can not or only poorly detected.