Rate coefficients and inelastic momentum transfer cross sections for electronic excitation of N2 by electrons

Abstract

Rate coefficients, as a function of the electron temperature, have been determined from the integral cross sections for excitation of the 19 singlet and triplet electronic states of N2 within 14.2 eV of the ground state. For electron temperatures less than 10 eV, the rates for excitation of the A 3Σ+u, B 3Πg, W 3Δu, and a 1Πg are all greater than that for excitation of the C 3Πu state. The differential cross sections for excitation of these same electronic states were also used to calculate the inelastic momentum transfer associated with the excitation of these states. The total momentum transfer cross section for electrons in N2, as a function of the electron energy, was obtained by adding the inelastic momentum transfer to that associated with elastic scattering. Inelastic momentum transfer accounts for about 25% of the total momentum transfer above 15 eV. Over the energy range 20–60 eV, inelastic scattering contributes 20–25% to the total N2 electron scattering cross section. The total scattering cross section obtained here is in good agreement with a recent direct measurement of this cross section.