Breit–Pauli Oscillator Strengths, Lifetimes and Einstein A Coefficients in Singly Ionized Sulphur

Energy levels, oscillator strengths and transition probabilities for a portion of the S II spectrum up to and including 3p2(1D)3d 2D3/2 were computed using the multiconfiguration Hartree–Fock (MCHF) method with relativistic effects included in the Breit–Pauli (BP) approximation. While term mixing in this spectrum is small, the 1D, 1S and 3P parents of the 3p23d configuration states were found to be highly mixed for many terms. Aki values for E1 and some E2 and M1 transitions were computed from which lifetimes for excited states were determined. The energy levels are analyzed by comparison with observation and transition probabilities compared with available theory. The lifetimes for 3s3p4 4P levels are in excellent agreement with experiment.

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