# Charge Transfer in Collisions Involving Symmetric and Asymmetric Resonance

W. L. Fite, A. C. H. Smith, R. F. Stebbings

## Abstract

The cross-sections for charge transfer in collisions between atomic hydrogen and O$^+$ and He$^{2+}$ ions are presented. Unique interest attaches to these processes because they may occur with small or zero energy defect. Theoretical conflict exists regarding the magnitude and energy dependence of the cross-sections for accidental resonance collisions; the present work was prompted by the need for further information. Cross-sections for symmetric resonance charge transfer between protons and atomic hydrogen are also presented for energies down to 20 eV. The experiments were carried out by means of the techniques of modulated crossed beams.