Relative line strengths have been computed for the transition arrays of 3p54s–3p54p and 3p54s–3p55p in Ar I. Intermediate-coupling theory has been used, starting from LS coupling, and using the experimental energy levels as data for determining the parameters of the theory by least-squares adjustment of the calculated energies. The results have been placed on an absolute scale using the Coulomb approximation. The Landé g factors computed agree well with the observed values. The calculated transition probabilities are in fairly satisfactory agreement with various experimental determinations, and this agreement is better than that obtained using either LS- or jl-coupling calculations. The results for the 4s–4p array appear to be more accurate than those for the 4s–5p array.
R. H. GARSTANG and JANET VAN BLERKOM, "Transition Probabilities in the Ar I Spectrum," J. Opt. Soc. Am. 55, 1054-1057 (1965)