Turbulence excited by the electron beam and evolution of current sheets near magnetopause magnetic reconnection regions

The current sheet and electron beam can be attributed to magnetic reconnection. Electron beams can further excite lower hybrid waves (LHWs). This paper presents a model to illustrate the evolution of LHWs (excited by an electron beam) and current sheets near magnetopause reconnection regions. We have developed a two-fluid model including thermal effects. The model is solved numerically to study LHW dynamics due to an energetic electron beam in the presence of magnetic islands. We used the pseudo-spectral method for spatial integration and the finite difference method with a modified predictor–corrector approach for time domain integration. The simulation results show that LHWs evolve from very small amplitudes (noise level) to higher levels due to beam energy. At higher amplitudes, ponderomotive nonlinearity and field perturbation due to magnetic islands lead the system to a turbulent state. We also discuss the spatiotemporal evolution of current sheets and the interplay between current sheets and LHWs for the beam-driven mode. From simulations, we anticipate that LHWs interact with current sheets and fragment them into small-scale structures. From this semi-analytic approach, we suggest that the dimensions of the current sheet may depend upon the wave mode, thermal effects, temperature profile and anisotropy.