Total cross sections for electron capture in slow Arq+/N2 (q = 6, 8) collisions

Abstract

Total charge transfer cross sections σ6, 6-i (i = 1-4) and σ8, 8-i (i = 1-6) have been measured in the energy range of 0.3-3.8 · q keV. Two different methods based on the crossed beam technique were used to determine the cross sections. One method is based on a retarding field analysis of the ion beam flux after the collision. The other method uses a coincidence technique in order to determine both, the dissociative part of the reaction and the total cross section. In the observed energy range all measured total cross sections have no significant energy dependence and both methods give the same results. The mean values of the cross sections are σ6, 5 = (32 ± 7) · 10−16 cm2, σ6, 4 = (8.4 ± 1.6) · 10−16 cm2, σ6, 3 = (8.4 ± 1.3) · 10−16 cm2 and σ6, 2 = (1.3 ± 0.2) · 10−16 cm2. In the system Ar8+/N2 the cross sections for the capture of i = 1, 2,..., 5 electrons amount to σ8, 8-i = (132, 38, 17, 13, 3.8) · 10−16 cm2, respectively.