Astrophysically relevant transitions in the Mg-like ions Si III, S V and Fe XV have been studied. A J -dependent CIV3 calculation, more extensive than other, earlier ones, has led to improved accuracy in the calculated energy levels and oscillator strengths. Independent relativistic quantum defect orbital and multiconfigurational Dirac-Fock calculations have also been performed. An analysis of the results is given.

Abstract. The relativistic quantum defect orbital method has been applied to the study of fine structure 5p2P-nd2D and 5pZP-ns2S (n > 5) transitions (some of them involving highly excited upper levels) in the silver isoelectronic sequence. The resulting oscillator strengths are analyzed in terms of other relativistic results and some available experimental data.

Abstract. in a very recent paper [1] we have reported oscillator strengths for fine structure transitions between levels belonging to the diffuse and sharp spectral series in the silver isoelectronic sequence. The calculations were performed with the quantum defect orbital method in both their non-relativistic (QDO) and relativistic (RQDO) formulations, with both implicit and explicit allowance for core-valence polarisation. We now present a parallel study of transitions belonging to the ns 2S-n' ZP(n = 5, 6; n' = 5-10) spectral series of the AgI sequence, up to Z = 63 in some cases.