Symmetric resonance multiple charge transfer of Ne^q+and Ar^q+(q⩽4)

Abstract

Cross sections for resonance charge transfer processes, Aq++A to A+Aq+, have been measured for Ne1-4+ and Ar1-4+ at ion acceleration voltages of 2, 3 and 4 kV. The cross sections obtained at 2 kV are 6.9*10-16, 1.74*10-16, 4.9*10-17 and 3.4*10-18 cm2 for Ne+, Ne2+, Ne3+ and Ne4+, respectively, and 2.4*10-15, 5.5*10-16, 9.0*10-17 and 3*10-18 cm2 for Ar+, Ar2+, Ar3+ and Ar4+, respectively. This is the first measurement of resonance charge transfer cross sections for quadruply charged ions. The results obtained are discussed in terms of the total ionisation energies Sigma jqIj of the ions, where Ij is the jth ionisation potential. A concept of the 'survival factor' is introduced.