Spectroscopy of highly charged ions: New studies in the He, Be, N, O, Na and Mg isoelectronic sequences

Abstract: Spectroscopic investigations of highly charged ions have been performed in the VUV, UV and visible spectral regions using mainly the beam-foil technique. New 2s22px3l levels have been established in N and O-like Si and S, together with many transitions between these levels. Several of these lines have also been identified in the solar corona spectra recorded by the SUMER/SOHO instrument. In Mg-like Sc - Fe the 2p63l4l' configurations have been determined using spectra from a laser-produced plasma. A previously noted discrepancy between the theoretical and experimental lifetime of the 3p 2P3/2 level in Na-like Kr has been resolved by new measurements. Configuration interactions have been studied in Be-like O. Detailed spectroscopic investigations of He-like N and O, aimed at determining the QED contribution to the ground state binding energy, have been performed. The experimental results show significant deviations from the theoretical predictions. Modifications of the beam-foil experimental set-up at Lund University Pelletron laboratory are described.