Elastic and inelastic scattering of electrons from Ar and Cl

Abstract
We have carried out extensive calculations of elastic and inelastic scattering of electrons from neutral argon and chlorine. The elastic and excitation cross sections are determined from the R-matrix method, in which the effects of dipole polarizability are included through the use of polarization pseudostates within the close-coupling expansions. For elastic scattering, our cross sections for Ar are compared to a number of other calculations and measurements. This provides a measure of the reliability of similar calculations for Cl. Our calculations of excitation include only transitions to the metastable levels of these atoms, where polarization effects are found to be quite important. Finally, ionization cross sections for these atoms are determined using the distorted-wave approximation; here, final-state correlation effects are found to be large.