Wannier electron capture to form doubly excited states of He and He –

Abstract

In this paper we present a complete account of our belowthreshold semiclassical theory for the study of doubly excited states. This theory, derived by the analytic continuation of Crothers abovethreshold theory, relies on a complex BohrSommerfeld quantization rule in order to determine the complex eigenenergies of the highlying doubly excited states of the negative ion He and atomic He. The Wannier ridge resonant positions of He for both intrashell and intershell states are presented for L 0 with an extension to include resonant states for L 1 and L2, where L is the total angularmomentum azimuthal quantum number of the two excited electrons. The intensities of these states have been estimated from the explicit widths given by the imaginary parts of the eigenvalue. For He, with core charge Z 2, the intrashell and intershell S resonance energy positions are also presented for values of principal quantum number up to n 15.