Mean Lives of Some Doubly Excited Levels in Lithium I

Abstract

Three doubly excited levels in Li I produced upon passage of 56-keV $^{7}\mathrm{Li}$ ions through a thin carbon foil have been identified. Their mean lives were measured using the beamfoil technique with the results given below: ${\ensuremath{\tau}(1s2{p}^{2} ^{4}P)=(6.4\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9} sec,}{\ensuremath{\tau}(1s2s3s ^{4}S)=(9.7\ifmmode\pm\else\textpm\fi{}0.7)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9} sec,}{\ensuremath{\tau}(1s2s3d ^{4}D)=(4.5\ifmmode\pm\else\textpm\fi{}0.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9} sec.}$