Fine-structure calculation of energy levels, oscillator strengths, and lifetimes in Al-like sulfur

Energy splittings of 54 fine-structure levels as well as oscillator strengt hs and transition probabilities for 395 transitions among the fine-structur e levels of the terms belonging to the 3s(2)3p, 3s3p(2), 3s(2)3d, 3p(3), 3s 3p3d, 3s(2)4s, 3s(2)4p, 3s(2)4d, 3s(2)4f, and 3s3p4s configurations of S IV are calculated using extensive configuration-interaction wave functions. T he relativistic effects in intermediate coupling are incorporated by means of the Breit-Pauli Hamiltonian. Small adjustments to the diagonal elements of the Hamiltonian matrices have been made so that the energy splittings ar e as close as possible to the experimental values. From our transition prob abilities, we have also calculated radiative lifetimes of doublet states in S rv. Our calculated energy levels and lifetimes are compared with other t heoretical and experimental results.