Photo double ionization of He: C3-like wave function for the two electron continuum

Abstract

We evaluate the triply differential cross-section (TDCS) for photo double ionization of helium. We use a C3 final continuum wave function with an interelectronic effective coordinate to express the nuclear screening. Comparison with the standard C3 model shows that the TDCS is enhanced in the threshold region by effect of the reduced interelectronic repulsion introduced by the present model. A more accurate description of the intermediate energy region is also obtained. Comparison with recent experimental data shows a good overall agreement of the angular distributions. The theoretical PDI total cross-section shows a relevant improvement in the intermediate energy region relative to the C3 model, which converges to data for photon energies larger than 1 keV.