Differential cross sections for the electron-impact excitation of the first ten electronic states of ${\mathrm{N}}_2$ have been determined at five incident energies ranging from 15 to 50 eV. These differential cross sections were obtained for the scattering range 10°–90° by analyzing electron-energy-loss spectra in ${\mathrm{N}}_2$ at a number of fixed scattering angles within that range. The present study represents a comprehensive remeasurement of the earlier work of Cartwright and co-workers [Phys. Rev. A 16, 1013 (1977)] and was undertaken with a view to resolving certain anomalies which have been reported in the literature when the earlier cross-section set has been applied to model calculations of swarm parameters.

• Received 13 April 1989

DOI:https://doi.org/10.1103/PhysRevA.41.1413