R-matrix description of charge transfer to continuum atomic states

Abstract

Charge transfer reactions to the continuum lead to three-body final states, for which a Faddeev-type theory (1960) is suitable. An alternative treatment is described in terms of the R-matrix theory of final-state interactions. This provides an explicit form for the cross section in terms of spectroscopic data, namely energy eigenvalues and reduced widths. A fit is obtained to the velocity spectrum of electrons from charge transfer to protons in carbon. This agrees satisfactorily with observed 'cusp' spectra and is consistent with observed data on the excitation function for the charge transfer reaction.