Energies and Lifetimes of the Metastable Autoionizing(1s2s2p)PJ4States ofLi6andLi7; Assignment of Li-IbQuartet Lines

A Zeeman-quenching atomic-beam method has been developed and used for the determinations of the energies and lifetimes of the metastable autoionizing $\mathrm{}\left(1s2s2p\right)\mathrm{}{}_{}{}^4{}_{}{}^{}P$ states of ${\mathrm{Li}}^6$ and ${\mathrm{Li}}^7$. The values obtained for certain of these parameters are in serious disagreement with existing theoretical estimates. The energy values have been used for the definitive identification of previously unassigned lines in the Li spectrum.