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: $\left\{\tau \right(1s2\mathrm{}{p}^2 {}_{}{}^4{}_{}{}^{}P)=(6.4\mathrm{}\pm 0.3)\times {10}^{-9\mathrm{}} sec,\}\left\{\tau \right(1s2s3s {}_{}{}^4{}_{}{}^{}S)=(9.7\mathrm{}\pm 0.7)\times {10}^{-9\mathrm{}} sec,\}\left\{\tau \right(1s2s3d {}_{}{}^4{}_{}{}^{}D)=(4.5\mathrm{}\pm 0.4)\times {10}^{-9\mathrm{}} sec.\}$