Theoretical treatment of state-selective one-electron capture by S 3+ ions in collisions with helium

Abstract

Ab-initio potential energy curves and coupling matrix elements of the molecular states involved in the collision of the S 3+ multicharged ion on helium have been determined by means of configuration interaction methods. The total and partial electron capture cross sections for the S 3+/He system have been determined using a semi-classical method in the 2–50 keV laboratory energy range. The results show a decrease of the cross-section on the S 2+( 1D) level for increasing collisional energy, in good agreement with experimental data.