Kinetic Alfven Waves in Space Plasma Environment with κ-electrons

A resonant instability of kinetic Alfven waves (KAWs) driven by ion beam is discussed through a theoretical model encompassing Maxwellian background ions and beam ions and non-Maxwellian kappa-electrons. The ion beam velocity alone as a source is able to excite the KAWs up to a significant growth. The non-Maxwellian parameter kappa impedes the growth of KAWs by restricting the wave unstable region. The effects of other plasma parameters such as propagation angle, temperature of the plasma species, and ion plasma beta on the excitation of KAWs are also examined. The present model can generate waves with frequencies in the range of approximate to 6.6-51.2 mHz, which are relevant to explaining the observed ultralow frequency waves at auroral ionospheric altitudes. Theoretical model predictions will also be applicable to other planetary environments where ion beams and non-Maxwellian kappa-electrons are present.

Automated summary

A theoretical model discusses the resonant instability of kinetic Alfven waves (KAWs) driven by ion beam and how non-Maxwellian kappa-electrons impede the growth of KAWs. The model also examines the effects of other plasma parameters on wave excitation and can generate waves with frequencies relevant to auroral ionospheric altitudes. Predictions from the model are applicable to planetary environments with ion beams and non-Maxwellian kappa-electrons.