Electron-impact ionization of N 2 at large momentum transfer above the double-ionization threshold

High-energy electron-impact ($e$,2$e$) measurements under large momentum-transfer kinematics for molecular nitrogen are reported over an extended binding-energy range. These measurements are supplemented with symmetry-adapted cluster configuration-interaction calculations to provide insight into the behavior of ionization mechanisms above the double-ionization threshold. Here, it was found that ionization-excitation processes make a significant partial contribution to the ionization phenomena for binding energies above the lowest double-ionization potential.