Differential cross sections and electron-impact coherence parameters for electron scattering from helium atoms

Abstract
We have applied the R-matrix with pseudo-states method (RMPS) to study electron - helium scattering at intermediate energies. Differential cross sections for elastic and inelastic collisions and electron-impact coherence parameters for excitation of the transition are presented for incident energies of 30, 50 and 80 eV. Excellent agreement with experiment and with the predictions of the convergent close-coupling calculation by Fursa and Bray is obtained. Since correlation effects and target continuum states are both accurately represented in a completely general way by this method, the associated program package can now be used to obtain reliable results at intermediate energies for arbitrary complex atomic and ionic targets of importance in applications.