Resonant charge transfer in He2+ + He+ collisions

Abstract

Employing the cross‐beams techique, we have measured absolute cross sections for charge transfer in collisions 3He2++4He+→3He++4He2+ in the centre‐of‐mass energy range between 4 keV and 200 keV.Reaction (1) is unique since it represents (i) a one electron collision system, (ii) a fully resonant electron‐capture process, and (iii) the simplest ion‐ion collisions system with Coulomb‐repulsion both in the incomming and the outgoing reaction channel.This process has been studied in the past by several groups, both theoretically and experimentally. All calculations are based on semiclassical, two‐state approximations and predict total cross sections with maximum values of about 8⋅10−6 cm2 at center‐of‐mass energies near 100 eV.Previous experimental results at energies 10 eV≤Ecm≤20 keV must be regarded however as partial cross sections, since the detection of the reaction products suffered from limited detector acceptances due to considerable scattering during the collision.The present results are in good agreement with theoretical predictions of Dickinson and Hardie, and they coincide with scaled cross sections for the reaction H++H→H+H+.Employing the cross‐beams techique, we have measured absolute cross sections for charge transfer in collisions 3He2++4He+→3He++4He2+ in the centre‐of‐mass energy range between 4 keV and 200 keV.Reaction (1) is unique since it represents (i) a one electron collision system, (ii) a fully resonant electron‐capture process, and (iii) the simplest ion‐ion collisions system with Coulomb‐repulsion both in the incomming and the outgoing reaction channel.This process has been studied in the past by several groups, both theoretically and experimentally. All calculations are based on semiclassical, two‐state approximations and predict total cross sections with maximum values of about 8⋅10−6 cm2 at center‐of‐mass energies near 100 eV.Previous experimental results at energies 10 eV≤Ecm≤20 keV must be regarded however as partial cross sections, since the detection of the reaction products suffered from limited detector acceptances due to considerable scattering during the collision.The present results are in good agre...