V-potential double layers and the formation of auroral arcs

A simulation study of the electrostatic interaction of a field-aligned electron current sheet with ambient hot ions (T/sub e//T/sub i/< or approx. =0.6) and a conducting boundary shows that a V-shaped potential double layer spontaneously develops and accelerates electrons to the ion thermal energy. It is proposed that this double-layer process is responsible for the aurora energy supply. Only as T/sub e//T/sub i/ approaches unity, the potential exceeds T/sub i/ via resistivity enhanced by wave trapping of electrons