A mechanism for energizing electrons in the magnetosphere

An electrodynamic heating mechanism is proposed to account for the precipitation of kilovolt energy electrons during an auroral disturbance. It is shown that given the existence of an electric field transverse to the geomagnetic field caused by space charges in the magnetosphere, currents will flow along the magnetic field connecting the space charges to the conducting ionosphere. It is shown that the longitudinal current deduced from magnetic observations can be of sufficient intensity to become unstable, resulting in growing ion acoustic waves. In the nonlinear limit these waves tend to inhibit current flows in a collisionless plasma and transform the ordered flow energy into turbulent energy, thus resulting in extreme electrodynamic heating of the electrons. The flow of these ‘hot’ electrons down the geomagnetic field lines is believed to be responsible for the bright aurora and accompanying ionospheric absorption.