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Cowan code: 50 years of growing impact on atomic physics



Alexander Kramida


The famous Cowan's book "The Theory of Atomic Structure and Spectra" published in 1981 and his suite of computer codes based on it continue to be highly influential in atomic physics and many other researchareas. As of September 2018, there are more than 5000 citations to Cowan's book and codes, and eachyear adds about 150 citations to this list. I will briefly describe what these codes do and why they areresponsible for most of the current progress in analyses of atomic spectra. Various modificationsof thesecodes, including my own, will also be described.


Atomic codes, atomic theory, Slater parameters, energy levels, least-squares fit


Kramida, A. (2019), Cowan code: 50 years of growing impact on atomic physics, Atoms, [online],, (Accessed April 24, 2024)
Created July 2, 2019, Updated April 30, 2021