A heuristic procedure to go from LS to jj expressions in atomic and nuclear spectroscopy


  • Julio C. Aguiar Autoridad Regulatoria Nuclear,
  • Héctor Oscar Di Rocco Retired (from Departmento de Física, Facultad de Ciencias Exactas, Universidad Nacional del Centro, Tandil, and CIFICEN (CONICET-CICPBA, UNCPBA, Argentina).




LS coupling, jj coupling, energy levels, radiative transitions


The expressions for the energy matrix elements and for the radiative transitions in the jj coupling can be obtained from the respective LS expressions by making a few simple changes. The results shown as examples are compared with other treatments, where the two formulations are deduced in parallel, without making use of these simple rules. We emphasize that the rules were found by heuristic reasoning. In all cases the application of the rules are in accordance with published results. This work completes two previous papers published in this journal (References 19 and 20).


i. In the middle of the year 2021, there have been more than 5500 citations to Cowan’s book and codes, and each year adds about 150 citations to this list.

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How to Cite

J. C. Aguiar and H. O. Di Rocco, “A heuristic procedure to go from LS to jj expressions in atomic and nuclear spectroscopy ”, Rev. Mex. Fis. E, vol. 19, no. 2 Jul-Dec, pp. 020201 1–, Apr. 2022.