Radiative lifetime and oscillator strength determination in potassium ions (K V, K VI and K VII)

Oscillator strengths have been calculated for the transitions depopulating levels of the 3s23p3, 3s3p4 configurations of K V, of the 3s23p2, 3s3p3 configurations of K VI and of the 3s23p, 3s3p2, 3p3 and 3s3p3d configurations of K VII. A multiconfiguration Dirac-Fock method, incorporating the relativistic two-body Breit interaction and quantum electrodynamics corrections due to self-energy and vacuum polarization, has been used for the calculations. The reliability of this approach has been tested by comparison with relativistic Hartree-Fock calculations and also with some experimental measurements performed by beam-foil spectroscopy at a beam energy of 1.7 MeV.