Doubly Excited Autoionization Resonances in the Absorption Spectrum ofLi+Formed in a Laser-Produced Plasma

Abstract

In a technique using a continuum generated by focusing a laser beam on a target of high atomic number, the spatially resolved absorption spectrum of ${\mathrm{Li}}^{+}$ formed in a second laser-produced plasma was studied from 200 to 50 Å. The doubly excited resonances, $1s^2{}_1{}^{}{}_{}{}^{}S-2\mathrm{snp}{}_{}{}^1{}_{}{}^{}P$, as well as the principal series and its adjoining photoionization continuum were observed. The Fano parameters, $q$ and $\Gamma$, of the $2s2p{}_{}{}^1{}_{}{}^{}P$ were derived from the absorption profile. Comparison is made with theory.