Far-UV spectroscopy of highly ionised argon using complementary techniques

Abstract

Far-UV spectroscopy of highly ionised argon has been studied with particular attention paid to core-excited metastable states. Excitation by foil-excited MeV beams is compared with single- and double- electron capture into excited states during low-energy charge exchange of highly ionised argon ions in helium and hydrogen targets. Complementary techniques are used for a) line identification by the high charge-state selectivity of the charge-exchange process, b) lifetime measurements, c) considerations concerning different excitation and cascade processes involved, d) systematics along isoelectronic sequences, and e) model-potential and MCDF calculations. A number of new lines are reported.