Simulation study on the nonlinear EMIC waves
Abstract
Nonlinear evolution of EMIC waves accompanying particle heating and the electromagnetic fluctuation spectrum associated with the drift Alfven-cyclotron (or EMIC) instability related to a current disruption event is investigated by means of PIC simulation. It is shown that parametric decay processes lead to an inverse cascade of EMIC waves and the generation of ion-acoustic waves by decay instability. It is found that the nonlinear decay processes accompany small perpendicular heating and parallel cooling of the protons, and a pronounced parallel heating of the electrons. The simulation shows that the drift Alfven-cyclotron instabilities are excited in two frequency regimes, a relatively low frequency mode propagating in a quasi-perpendicular direction while the second high-frequency branch propagating in a predominantly parallel propagation direction, consistent with observations as well as with a recent theory.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFMSH21B2210R
- Keywords:
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- 2114 INTERPLANETARY PHYSICS / Energetic particles;
- 2772 MAGNETOSPHERIC PHYSICS / Plasma waves and instabilities;
- 4455 NONLINEAR GEOPHYSICS / Nonlinear waves;
- shock waves;
- solitons;
- 7839 SPACE PLASMA PHYSICS / Nonlinear phenomena