Molecular Effects in Beam-Foil Electron Transfer to the Continuum

Distributions of electrons emitted when thin carbon foils are bombarded with H⁺ and H₂⁺ ion beams are measured along the forward direction and close to the projectile velocity. The ratio between electron yields per proton for H₂⁺ and H⁺ projectiles grows from unity away from the electron peak to a maximum at the peak. This explains the narrower peak widths observed for molecular projectiles. The results are interpreted in terms of a correlated action of the emergent protons on the process of electron transfer to the continuum.