Journal article
State selective singlephoton double ionization of Ne indicating singlettriplet mixing of doubly excited LSstates
Publication Details
Authors:  Kilin, V.; Lazarev, D.; Lazarev, D.; Amusia, M.; Schartner, K.; Ehresmann, A.; Schmoranzer, H.

Journal:  Journal of Physics B: Atomic, Molecular and Optical Physics 
Abstract
The stateselective doublephotoionization cross sections of the NeIII 2s^{2}2p^{4} [^{3}P,^{1}D,^{1}S], 2s^{1}2p^{5} [^{3}P,^{1}P] and 2s^{0}2p^{6} [^{1}S] states in the excitingphoton energy region from 60 up to 200eV are calculated with the use of V^{(N1)} and V^{(N2)} potentials. To our knowledge, the basis of wavefunctions obtained with the use of the V^{(N2)} potential is employed for the first time for the calculation of the total DPI cross section of a manyelectron atom. The lowestnonvanishingorder perturbation theory V^{(N2)} cross sections are compared with V^{(N1)} ones and with theoretical results of other authors. The obtained results show that the V^{(N1)} potential overestimates and the V^{(N2)} potential underestimates the experimental total DPI cross section of the L shell in Ne. The best agreement with experiment is achieved for the sum of the 2s^{1}2p^{5} and 2s^{0}2p^{6} stateselective V^{(N2)} velocityform cross sections. The necessity of including the higherorder correlations, especially those responsible for singlettriplet mixing of the final doubly excited states, is demonstrated and discussed.