Jumps and bi-stabilities in electron energy distribution in Ar-N-2 post discharge plasma

The electron energy distribution function (EEDF) in an afterglow of a pulse d direct current discharge has been measured in an Ar:N-2 mixture by means of a time-resolved Langmuir probe technique. The vibrational temperature, T -nu, of N-2 molecules has also been experimentally estimated. The results s how that a correlation between an effective electron temperature, T-e, and T-nu strongly varies with experimental conditions. In particular the condit ions exist under which the rapid decrease from high to low T-e values is ob served at some moment after the discharge pulse, while the vibrational temp erature remains almost constant. The theoretical study of the EEDF in Ar:N-2 afterglow plasma has also been made by the numerical solution of an appropriate Boltzmann equation by taki ng into account electron-electron collisions as well as superelastic vibrat ional and superelastic electronic collisions. Calculations show that for a given T-nu the value of T-e depends on the electron concentration, n(e). Mo reover, the ranges of n(e) and T-nu exist, where two different solutions of Boltzmann equations can be obtained. Finally, the comparison of the theoretical and experimental results is perf ormed and an explanation of the experimentally observed phenomenon is given .