Autoionization of the Ne+ Rydberg states formed via valence photoemission

Autoionization decay from Ne+ Rydberg states has been investigated by using multi-electron spectroscopy at a photon energy of 200.4 eV, where the autoionizing states have been produced through valence photoemission with simultaneous excitation into Rydberg orbitals. The coincidence measurements enable one to resolve individual autoionization lines corresponding to decays from the Ne+ 2p−2(1D)nl, 2p−2(1S)nl, 2s−12p−1(1,3P)nl and 2s−2(1S)nl Rydberg states. The present investigation revealed the autoionization decay features of the Rydberg states: branching ratios, which show strong selectivity towards the Ne2+ final states and asymmetric line shapes in the electron spectra, which have been analysed in terms of the interaction between the discrete state and each continuum. In addition, it is demonstrated that the autoionization decay feature of the Ne+ 2s−12p−1(1P)3p 2S state is characterized by a strong interaction with 2s−12p−1(3P)nl autoionizing states.