[PEM15-P23] Electron inertia effect on the feedback instability in the magnetosphere-ionosphere coupling system
Keywords:Aurora, magnetosphere-ionosphere coupling, Alfven wave
In this research, we have added the electron inertia term to the reduced-MHD model to introduce the parallel electric field (Epara) along field lines. As Epara can accelerate electrons, the new model enables us to describe the growth of auroral arcs and the electron acceleration simultaneously in a numerical simulation.
As the first step, we have analyzed the linear dispersion relation including the electron inertia effect, and compared the linear frequency and growth rate with those obtained from the conventional model. It turns out that the lower frequency is found for the higher wave number while the growth rate is smaller in the former for all wavenumbers. We have also examined Epara and energy transfer rate dependence on the magnetospheric height and on the perpendicular wave number (kperp). The results show that Epara works as acceleration in case with a positive growth rate, and vice versa. Furthermore, we will show the results of nonlinear simulation in the presentation.