Electron capture by He²⁺ions in collisions with H and H₂at impact energies below 10 keV

Total cross sections for the process He 2+ +H(1s) to He + ( Sigma n,l)+H + involving capture into all final bound states of He + have been determined for 3 He 2+ ions in the range 1.5-9.0 keV using a furnace-target technique previously employed for similar measurements at higher impact energies. Measured cross sections are considerably smaller than those measured previously by Fit et al. (1962) and are in better accord with recent theoretical estimates. A likely explanation for the discrepancy is given in terms of the corresponding cross sections for electron capture in He 2+ -H 2 collisions which have also been determined.