BEAM GENERATED ’LEFs ’ IN THE AURORAL PLASMA

A theoretical investigation is carried out of the instabilities associated with a model applicable to the auroral acceleration region consisting of an ion beam, precipitating electrons and stationary background electrons. The kinetic dispersion relation is solved numerically without any ap-proximations for auroral plasma parameters. It is shown that low-frequency plasma instabilities are present, which can generate the low-frequency electric field fluctuations (LEFs) that have been observed in the auroral acceleration region. A detailed parameter study of the instability as a function of plasma parameters, such as particle densities and drift speeds, is conducted. 1