Radiative lifetimes of the first excited 3P2,0o metastable levels in Kr I, Xe I, Yb I and Hg-like atoms

Abstract In the present work we have closed certain important gaps in the available data on theoretical radiative lifetimes of the metastable 3 P 2,0 o levels arising from the first excited configuration of Kr I, Xe I, Yb I and Hg-like atoms. All the possible radiative decay modes of the 3 P 2,0 o levels in these atoms have been comprehensively discussed, transition rates for the dominant decay channels calculated and finally, the theoretical lifetimes of the metastable levels arrived at. As a spin-off, the potential importance of some of the transitions ( 3 P 0 o → 3 P 1 o in rare gas atoms or 3 P 2 o → 3 P 1 o in Hg-group) for developing IR lasers is inferred and the peak gain coefficient for the proposed laser transitions are calculated.