Charge transfer in low-energy collisions of ${\mathrm{He}}^{2+}$ with atomic hydrogen

Charge transfer in low-energy collisions of ${He}^{2 +}$ with atomic hydrogen

C. C. Havener, R. Rejoub, P. S. Krstić, and A. C. H. Smith

Phys. Rev. A 71, 042707 – Published 19 April 2005

Abstract

Using the Oak Ridge National Laboratory ion-atom merged-beams apparatus, absolute total charge-transfer cross sections have been measured for collisions of ${He}^{2 +} + H$ over a range of energies from $380 to 2620 eV ∕ u$ . The experimental results are compared to previous measurements using different experimental techniques. A hidden-crossing coupled-channel (HCCC) calculation is performed in the collision energy range of $10 to 3000 eV ∕ u$ and is compared with the measured data as well as with other theories. The HCCC calculation, which is deemed accurate below $1000 eV ∕ u$ , is also used to determine differential cross sections. The resultant angular scattering information is used to correct the merged-beams data, which is characterized by a large but limited angular acceptance at these collision energies. Our combined experimental and theoretical study provides an improved benchmark for this fundamental system.