Spectroscopic study of doubly excited levels in NeVII** and NeVIII**

The emission spectra of Ne6+ and Ne7+ ions generated by beam-foil excitatio n in the range 18-48 nm show a number of lines arising from doubly excited levels. Hartree-Fock calculations using superpositions of quasi-degenerate configurations provided many of the identifications, as did interpolations along the lithium-like and beryllium-like isoelectronic sequences. From the se observations, energies of Ne (VII) 1s2s2pnl and 1s2p(2)n'l' configuratio ns are derived for the n = 3 and 4 levels. This has led to a revision of se veral Ne v(II) levels previously reported in the literature. In addition, s even new 3d-4f transitions were found between doubly excited states in lith ium-like Ne v(III)**.