X-ray spectroscopy

X-ray spectroscopy consists of three steps: (a) excitation to produce emission lines characteristic of the elements in the material, (b) measurement of their intensity, and (c) conversion of X-ray intensity to concentration by a calibration procedure which may include correction for matrix effects.
PAC, 1980, 52, 2541 (Nomenclature, symbols, units and their usage in spectrochemical analysis - IV X-ray emission spectroscopy) on page 2544