Many-electron aspects of molecular promotion in ion-atom collisions: Production of core-excited states of Li inLi+-He collisions

Production of core-excited autoionizing states of neutral Li having configurations of the form $1snl{n}^{\prime }{l}^{\prime }$ has been observed over the impact-energy range from 10-50 keV. Although the results for production of all such states is remarkably consistent with a quasimolecular-excitation model proposed by Stolterfoht and Leithäuser, production of individual lines in the observed spectra exhibits collision-velocity dependencies indicative of considerably more complex processes, including processes which appear to be inherently two electron in nature. Excitation functions are presented for the $\left(1s2\mathrm{}{s}^2\right){}_{}{}^2{}_{}{}^{}S$, $1s\left(2s2p{}_{}{}^3{}_{}{}^{}P\right){}_{}{}^2{}_{}{}^{}P$, $1s\left(2s2p{}_{}{}^1{}_{}{}^{}P\right){}_{}{}^2{}_{}{}^{}P$, and $\left(1s2\mathrm{}{p}^2\right){}_{}{}^2{}_{}{}^{}D$ core-excited states of Li and for total core excitation.