Charge exchange betweenH(2s)and fully stripped carbon and nitrogen ions at low-keV impact energies

Abstract

Approximate cross sections for charge transfer between $\mathrm{H}\mathrm{}\left(2s\right)\mathrm{}$ and fully stripped carbon and nitrogen ions have been obtained in the velocity range 6 × ${10}^6$-7 × ${10}^7$ cm/sec. In these systems, transfer takes place into high-lying orbitals of the final-state ion. The Landau-Zener theory modified for application to a multistate system is used to calculate the cross sections. The coupling-matrix elements are determined both from a study of the pseudocrossings observed in the relevant system of the adiabatic potential curves and by direct calculation using the appropriate asymptotic parabolic wave functions. The resulting cross sections are large, in the ${10}^{-14\mathrm{}}$-${\mathrm{cm}}^2$ range for both ${\mathrm{C}}^{+6\mathrm{}}$ and ${\mathrm{N}}^{+7\mathrm{}}$, and show the relatively flat energy dependence characteristic of systems with a number of contributing curve crossings.