Three-Body Coulomb Problem Probed by Mapping the Bethe Surface in Ionizing Ion-Atom Collisions

Abstract

The three-body Coulomb problem has been explored in kinematically complete experiments on single ionization of helium by 100 MeV u C61 and 3.6 MeV u Au531 impact. Low-energy electron emission (Ee , 150 eV) as a function of the projectile deflection qp (momentum transfer), i.e., the Bethe surface [15], has been mapped with Dqp 6 25 nanoradian resolution at extremely large perturbations (3.6 MeV u Au531) where single ionization occurs at impact parameters of typically 10 times the He K-shell radius. The experimental data are not in agreement with state-of-the-art continuum distorted wave–eikonal initial state theory.