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In this paper we have applied a semi-empirical theory of Mihajlov and Pivovar to calculate the cross sections and rate coefficients for excitation from one vibrationally excited level (v) of nitrogen to another (k). Calculations were performed for 0 v, k 8, which is the limit set by the applicability of the model. The semi-empirical model assumes that the process of excitation to a higher vibrationally excited state may be split into two separate parts, which is justified if the lifetime of the negative ion compound state is much longer than the flight time of the projectile electron across the dimension of the molecule. The semi-empirical model calculations were based on the best available experimental data for elastic scattering of electrons and vibrational excitation from the ground state. Results for all combinations of the vibrational quantum numbers were obtained. Both Maxwellian and non-equilibrium rate coefficients were determined and it was found that there is a great difference between the two sets of coefficients due to a very specific shape of the electron energy distribution function in nitrogen at moderate E/N (where E is electric field and N is gas number density).

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The authors present measurements of the electron energy distribution functions (EEDF) for electrons in argon discharges at moderate and high E/N values (E being the electric field and N the gas density), for homogeneous electric fields and a low-current diffuse glow regime. Results were obtained for electric field to gas density ratios (E/N) from 500 Td to 50 kTd (1 Td=10-21 V m2). A multigrid energy analyser with a retarding grid potential was used to measure distribution functions of electrons sampled through an aperture in the anode. Experimental data are used to make a comparison with the two-term Boltzmann calculations for E/N<1 kTd, and the single-beam model predictions, normally used to model electron kinetics at high values of E/N.