On the relation between magnetic field-aligned electrostatic electron acceleration and the resulting auroral energy flux

Supra-thermal electron fluxes measured above auroral arcs aboard two Porcupine sounding rocket payloads in 1977 and 1979 were used to study the relation between the acceleration potential difference as deduced from the position of the peak in the energy spectrum and the resulting electron energy flux. It was found, contrary to the findings of other authors, that the dependence of the energy flux on the acceleration voltage could be described by a linear relationship to a good approximation, above discrete auroral arcs. A stronger dependence of the energy flux on the acceleration voltage was however observed near the edges of auroral forms. Supported by model calculations, the suggestion is put forward that different distribution functions of the source electron populations might be responsible for the change of the relationship.