Dynamical screening effects on single ionization of helium by 102 eV electron impact

Institute of Modern Physics, College of Physics and Information Engineering, Shanxi Normal University Linfen 041004, PRC

Corresponding author: jiaxf@dns.sxnu.edu.cn

Received: 29 July 2008
Accepted: 27 August 2008

Abstract

In this paper, the dynamical screening three-Coulomb-wave (DS3C) model is applied to study the single ionization of helium by 102 eV electron impact. Triply differential cross-sections (TDCS) are calculated at different scattering angle  (8°, 10°, 15°, 20°) for both coplanar and perpendicular plane asymmetric geometries. Comparisons are made with experimental data and those of a three-Coulomb wave function (3C) model and a convergent close-coupling (CCC) model. The angular distribution and relative heights of the present TDCS are found to be in very good agreement with the experimental data in the perpendicular plane geometry. It is shown that three-body coupling effects are important in this geometry. Three-body coupling is expected to be weak in the coplanar geometry, although the precise absolute value of the cross-section is still sensitive to the interaction details.