This progress report descends from the report on doubly excited states of atoms presented at the first of these Conferences. 1 It develops the trend introduced at Belgrade last year2 toward a descriptive treatment of electron correlations by summarizing the results on doubly excited He and H obtained by one of us.3 It will also outline, in the initial section, the background problems of excitation dynamics which have lent special interest to the theory of doubly excited states from its very beginning.4 The progress achieved thus far encourages us to articulate such broader problems, the more so as we are now beginning to discern how our approach to double excitation may eventually encompass the Wannier theory of threshold ionization and the transition to the Born and impulse approximations which are characteristic of higher-energy collisions. Remarks on this aspect will be made in a concluding section.
KeywordsSaddle Point Angular Correlation Channel Function Excite Electron Channel Coupling
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- 18.An analogous problem occurs in the motion of a single highly excited electron under the combined influence of a Coulomb and a magnetic field, in which case the Schroedinger equation involves two nonseparable variables only. Resonances observed near the ionization threshold [W. R. G. Garton and F. S. Tomkins, Astrophys. J. 158, 839 (1969)] have been interpreted in terms of excitation of a Wannier-like channel [A. F. Starace, J. Phys. B 6, 76 (1973)]. A treatment of this problem along the lines of the present paper and of ref. 3 is now being developed by A. F. Starace.Google Scholar