Excitation of the projectile helium ion impacting on hydrogen

Abstract

The Vainshtein-Presnyakov-Sobel'man approximation (VPSA) has been applied to calculate the 2s excitation cross section of projectile He+ in the reaction He+(1s)+H(1s)→He+(2s)H(1s). Calculations have been performed for both post and prior forms assuming the peaking approximation. Comparison is made with the existing theoretical calculations and experimental data. It is found that the VPSA (post form) cross sections agree reasonably well with the experimental data. The VPSA (prior form) is in disagreement with other theoretical calculations. At high energies all the theoretical calculations give identical results. © 1984 The American Physical Society.