Electron-impact electronic excitation of molecular nitrogen using the Schwinger multichannel variational method

The Schwinger multichannel method is applied to study the low-energy electron-impact excitation of molecular nitrogen. The scattering amplitudes are obtained within the minimal orbital basis for single configuration interactions (MOBSCI) level of approximation, for impact energies from near threshold up to 30 eV. Through the use of the MOBSCI strategy we have performed a close-coupling calculation for up to nine states, including the ground state and all singlet and triplet states resulting from the π_u→π_g transitions. Integral and differential cross sections for the X ¹Σ_g⁺→A ³Σ_u⁺, W ³Δ_u, B^′ 3Σ_u⁻, a^′ 1Σ_u⁻, and w ¹Δ_u electronic transitions are presented and compared with available experimental data and also with other theoretical results.