X-ray Emission or Proton Induced X-ray Emission (PIXE) is a technique used in
the determining of the elemental make-up of a material or sample. When a
material is exposed to an ion beam, atomic interactions occur that give off
EM radiation of wavelengths
in the x-ray part of the electromagnetic spectrum specific
to an element. PIXE is a powerful yet non-destructive elemental analysis
technique now used routinely by geologists, archaeologists, art conservators
and others to help answer questions of provenance, dating and authenticity.