Isoelectronic trends of the E1-forbidden decay rates of Al-, Si-, P-, and S-like ions of Cl, Ti, Mn, Cu, and Ge

Working towards a reliable grid of atomic lifetime data on 3s23pk ground configuration levels of Al-, Si-, P-, and S-like ions of iron group elements, measurements on electric-dipole forbidden decays in ions of Cl, Ti, Mn, Cu, and Ge have been done at a heavy-ion storage ring that complement earlier measurements on Fe, Co, Ni, and Cu ions. The data are compared isoelectronically with various predictions, especially those made by the multi-reference Møller-Plesset technique, and with the few results available from other experimental approaches. Apparent perturbations of otherwise smooth isoelectronic trends of some of the data are identified with the occurrence of specific cascades from long-lived 3d levels.