Radiative Lifetimes of Excited Levels in the Homologous Ions Ar II, Kr II and Xe II

Radiative lifetimes of nine of the levels np 4P5/20, np 4D7/2,5/20 and np 2D5/20 in the homologous ions Ar II (n = 4), Kr II (n = 5) and Xe II (n = 6) have been measured with the beam-laser method. The measured lifetimes are compared with lifetime values from other experimental and theoretical works and a thorough discussion of the discrepancies between the results obtained with different techniques is made. Older measurements of transition probabilities are put on an accurate scale using the new lifetime values. The f-values of some strong transitions from levels in the np configuration in Ar II, Kr II and Xe II are compared and are found to be approximately equal.