Effect of nonlinearity, magnetic islands on turbulence and observation of electron energization, temperature anisotropy at Earth’s magnetopause (magnetosphere)

Abstract

Space missions’ observations have shown that waves such as lower hybrid waves (LHWs), whistler waves, and kinetic Alfven waves play a vital role in magnetic reconnection, turbulence, and particle acceleration. This paper studies the effect of nonlinearity and the magnetic islands on lower hybrid turbulence and current sheets in Earth’s magnetopause region. The evolution of electromagnetic LHW has been studied with numerical model using pseudo-spectral method for spatial integration and finite difference method with modified predictor-corrector approach for temporal integration. We have considered both ion and electron dynamics and included electromagnetic and warm plasma effects in our model. The study outcomes reveal that both the nonlinear effects and magnetic islands are responsible for the evolution of LHWs and current sheets to a chaotic and turbulent state. We have also used the semi-analytical model to elaborate on the physics behind the localization. Finally, the nonlinear model with field perturbations (magnetic islands) is further used to elaborate on the electron energization and temperature anisotropy near reconnection regions. We have also discussed the relevance of model predictions in the context of the MMS mission observations at Earth’s magnetopause.