The triple differential cross section for double photoionization in helium has been measured for the first time. Equal energy sharing and a simple geometry for the two emitted electrons were chosen in order to facilitate the comparison with theory. Good agreement between experimental and theoretical data is found for the angular correlation pattern if the mutual Coulomb repulsion between both escaping electrons is taken into account.

• Received 21 January 1993

DOI:https://doi.org/10.1103/PhysRevLett.70.3008