Abstract
The photo-ionization cross sections of the and states of He were evaluated in the energy regions 0.20-2.40 Ry and 3.15-3.30 Ry. The 56-term bound-state wave functions obtained by Pekeris were used for the initial states. An expansion into a complete discrete basis set (a modification of the close-coupling method used in electron-atom scattering) was carried out for the final-state continuum wave functions. Particular attention was given to the processes where the ejected photoelectron leaves the ion in an excited state. The results obtained from the length and velocity expressions for the photo-ionization cross sections show an agreement to within 1% in the lower-energy region. Good accuracy is achieved for the negative-power moments of the oscillator-strength distributions.
- Received 8 July 1970
DOI:https://doi.org/10.1103/PhysRevA.3.289
©1971 American Physical Society