Dynamics of H+ + Kr and H+ + Xe elastic and charge-transfer collisions: State-selected differential cross sections at low collision energies.

Abstract

Elastic and charge-transfer scattering of protons by Kr and Xe targets has been investigated in a crossed-beam experiment at collision energies ${E}_{\mathrm{c}.\mathrm{m}.=30.6}$ and 51.7 eV. The charge-transfer collisions led to the formation of ${\mathrm{Kr}}^{+}$(${\mathrm{}}^{2}$${\mathrm{P}}_{3/2}$,${\mathrm{}}^{2}$${\mathrm{P}}_{1/2}$)+H(n=1) and ${\mathrm{Xe}}^{+}$(${\mathrm{}}^{2}$${\mathrm{P}}_{3/2}$,${\mathrm{}}^{2}$${\mathrm{P}}_{1/2}$)+H(n=1,n=2) products respectively. Interference patterns in the state-selected relative differential cross sections were clearly resolved and have been ascribed to primary and secondary rainbows and/or Stueckelberg-type oscillations. The ${\mathrm{H}}^{+}$+Xe collisions have also been investigated theoretically by the exact close-coupling method. A good agreement between theory and experiment has been found. A novel method for determining the absolute H-atom detection efficiency is suggested.