Hyperfine Structure and Intercombination Line Intensities in the Spectra of Magnesium, Zinc, Cadmium, and Mercury*

The transition probabilities of the lines 1S0–3P0 and 1S0–3P2 of the s2–sp arrays in Mg i, Zn i, Cd i, and Hg i, which arise by the interactions of the nuclear moments with the electrons, are computed for each odd isotope individually and for the naturally occurring isotopic mixture. The individual hyperfine structure component transition probabilities are given for the 1S0–3P2 lines. Part of the intensity of the lines arises from the interaction of 3P0 or 3P2 with 3P1 and part from the interaction of 3P0 or 3P2 with 1P1, the former being more important for 1S0–3P0 and the latter for 1S0–3P2. Spin-spin and spin-other-orbit interactions in Mg i are calculated for the 3s3p3P term and compared with observations.