Theoretical calculation of single ionization in collisions between protons and low-Zmolecules at intermediate and high energies

Abstract

Single ionization total cross sections for proton impact on ${\mathrm{N}}_{2},$ CO, ${\mathrm{CH}}_{4},$ and ${\mathrm{CO}}_{2}$ are calculated by applying the continuum-distorted-wave-eikonal-initial-state model. Two different approximations have been considered for molecular targets: Bragg's additivity rule and a molecular representation of the bound state target wave function. In the latter, the cross section is approximated by a linear combination of atomic cross sections where the coefficients are determined from a population analysis and the binding energies have been extracted from experimental spectra. The results from both models are compared with experimental data.