A model is constructed from a self-consistent solution of the Vlasov-Maxwell equations. The model has certain properties in common with auroral arcs. A pair of electric fields similar to the auroral electric fields is shown to be inherent to the electron current sheet in the model. The magnitude of the inherent fields is related to the width of the current sheet which in turn depends on the current density and the ion and electron energy densities. The potential energy associated with the inherent electric field is on the order of the ion thermal energy. These properties of the model are in qualitative agreement with the observed relationship between the width and the brightness of an auroral arc, and the relationship between the average energy of auroral electrons and the latitude.