Critical minimum in elastic electron scattering by krypton

Abstract

The position of the critical minimum in elastic electron–krypton scattering at intermediate electron energies was investigated. Differential cross sections (DCSs) were measured as a function of both incident electron energy (100–260 eV) and scattering angle (30–110°), in small steps around the critical minimum. The energy dependence of the angular positions of DCS minima were determined. Also, the positions of minima in energy-dependent DCSs were obtained at several fixed scattering angles close to the critical value. The position of the critical minimum was determined to be at 187.9 ± 0.5 eV and 83.0° ± 0.2°. However, the strong dependence of critical energy on small changes of critical angle was found. The obtained results are compared with the most recent theoretical calculations.