Mean life measurement of 4p and 4p′ levels in argon II using an image tube spectrograph

Abstract Lifetimes of eight 4p and four 4p′ levels in Ar II were measured using the beam-foil method and an image tube spectrograph. The experimental lifetime and transition probability measurements presently available for many of these levels are in disagreement. Our mean values for the 4p levels are slightly longer than those obtained by pulsed electron beams. Our beam-foil results, which include previously unreported Ar II lifetimes, are compared with experimental and theoretical values obtained by other techniques.