X-ray photoelectron spectroscopy

https://doi.org/10.1351/goldbook.X06716
Any technique in which the sample is bombarded with X-rays and photoelectrons produced by the sample are detected as a function of energy. ESCA (Electron @S05848@ for Chemical Analysis) refers to the use of this technique to identify elements, their concentrations, and their chemical state within the sample.
Source:
Orange Book, 2nd ed., p. 250 [Terms]