Halfway house variational continuum distorted waves and anisotropy in electron capture to the continuum: the Thomas double scattering limit

The halfway house phase-integral variational continuum distorted wave (PIVCDW) theory of non-relativistic Thomas double scattering electron capture is developed within the distorted wave perturbation approximation and has the distinct advantage of satisfying all well known short and long range boundary conditions. Closed analytical results are obtained for both first-order (PIVCDW1) and second-order (PIVCDW2) amplitudes of this theory for transitions from an initially excited n'l'm' state to a final nlm hydrogenic one-electron state. (Author)