F. Maulbetsch et Js. Briggs, THE ANGULAR-DISTRIBUTION OF EQUAL-ENERGY ELECTRONS FOLLOWING DOUBLE PHOTOIONIZATION, Journal of physics. B, Atomic molecular and optical physics, 26(19), 1993, pp. 647-652
The triply differential cross section (TDCS) for double photoionizatio
n of helium such that both electrons have the same energy is calculate
d for total energies of 10 eV and 20 eV above threshold. Excellent agr
eement with recent experimental results is obtained using a three-body
Coulomb (3C) correlated final-state wavefunction. Rather surprisingly
it is shown that an angular distribution calculated with plane waves
as the final state, multiplied by a Coulomb correlation factor arising
from the normalization of the electron-electron interaction, gives go
od agreement with the 3C results and therefore allows the shape of the
TDCS to be explained in a simple way. Some comments on a previous tre
atment using 'Wannier' theory are given.