Energy-averaged electron-ion momentum transport cross section in the Born approximation and Debye-Huckel potential: Comparison with the cut-off theory

An exact analytical expression for the energy-averaged electron-ion momentu m transport cross section in the Born approximation and Debye-Huckel expone ntially screened potential has been derived and compared with the formulae given by other authors. A quantitative comparison between cut-off theory an d quantum mechanical perturbation theory has been presented. Based on resul ts from the Born approximation and Spitzer's formula, a new approximate for mula for the quantum Coulomb logarithm has been derived and shown to be mor e accurate than previous expressions. (C) 2000 Elsevier Science B.V. All ri ghts reserved.