Exploring the helium (e, 2e) differential cross section at 64.6 eV with symmetric scattering angles but nonsymmetric energies

Helium (e, 2e) measurements are presented for an incident energy of 64.6 eV over a wide range of scattering angles from the coplanar to the perpendicular plane geometry. These measurements were taken for symmetric scattering angles and a range of detection energies from symmetric energy sharing where each electron has an excess energy of 20 eV to asymmetric sharing where the electrons have energies of 5 eV and 35 eV. A deep minimum observed for an electron gun angle of 67.5 degrees was explored as a function of this energy sharing.