Evidence for Two-Centre Effects in the Electron Emission from 25 MeV/u Mo ⁴⁰⁺ + He Collisions: Theory and Experiment

Abstract

Absolute doubly differential cross-sections for electron emission in 25 MeV/u Mo40+ + He collisions were measured as a function of the electron energy and emission angle. The data show enhancement at forward angles and reduction at backward angles with respect to results derived using the Born approximation. Comparison with a continuum distorted-wave approximation suggests that this observation can be explained by the combined influence of the projectile and target Coulomb fields on the ejected electron. This two-centre effect is found to be particularly important for electron emission at backward angles.