Electron Impact Excitation of Atoms

Abstract : The experimental and theoretical literature about the electron impact excitation of atoms is reviewed. Theoretical methods ranging from the Bethe and Born approximations to the close coupling approximations are discussed and intercompared. Where possible, on theoretical grounds or through intercomparison, the reliability of the various methods is discussed. A general critique of the optical method of measuring excitation functions is given, with the objective of promoting higher quality future experimental work. A critical study of existing experimental work leads to the conclusion that most workers have ignored important physical and instrumental effects, and it may be presumed that the data in the literature is subject to many unrecognized systematic errors. The literature on hydrogen and helium is discussed critically. The literature on the alkalis, heavy rare gases, mercury, cadmium and zinc is surveyed but the quality of the literature does not support critical review beyond some general comments about the physics of these atoms. (Author)