Self-Consistent Particle Simulation of Whistler-mode Chorus Emissions

Details Self-Consistent Particle Simulation of Whistler-mode Chorus Emissions Self-Consistent Particle Simulation of Whistler-mode Chorus Emissions

Dec 2006

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006agufmsm33a0346k&link_type=abstract

American Geophysical Union, Fall Meeting 2006, abstract #SM33A-0346

Physics

2720 Energetic Particles: Trapped, 2730 Magnetosphere: Inner, 2772 Plasma Waves And Instabilities (2471), 2788 Magnetic Storms And Substorms (7954), 7839 Nonlinear Phenomena (4400, 6944)

Scientific paper

The generation process of whistler-mode chorus emissions is simulated by a self-consistent particle code including the effect of the dipole magnetic field. Results of in-situ observations have revealed that the emissions which often consist of rising tones are generated from the equatorial region of the magnetosphere and that its activity is enhanced during geomagnetically disturbed periods. Theoretical analyses have also suggested that the generation process of chorus emissions is deeply related to the nonlinear cyclotron resonance with energetic electrons in a non-uniform magnetic field, and several models have been proposed to explain the generation mechanism. However, the spontaneous generation of a series of coherent rising tones from thermal noise of the plasma has been left as a mystery because the complexity of the nonlinear wave- particle interactions prevents studies without several simplifying assumptions. In the present study, we report the initial result of a self-consistent particle simulation reproducing VLF chorus emissions from the thermal noise. We use a simulation model by assuming a cylindrical field model, which enables us to solve the adiabatic motion of the energetic electrons due to the mirror force in the non-uniform magnetic field. As for the initial conditions of the simulation, we assume the energetic electrons having an anisotropic loss-cone velocity distribution which drives an instability generating narrow band whistler-mode waves. In the early stage of the simulation result, coherent whistler-mode waves propagating away from the equator are generated through the instability due to the anisotropic electrons. The coherent whistler-mode waves interact with counter-streaming energetic electrons and the emissions with rising tones are intermittently generated in the equatorial region of both hemisphere. This simulation result clarifies that the roles of the resonant currents formed by phase bunched untrapped electrons are essential in the generation mechanism of chorus emissions. Moreover, it is also demonstrated that the present simulation model has an enough potential to investigate the detailed physics of the whistler-mode chorus emissions.

Affiliated with

Also associated with

No associations

Rating

Self-Consistent Particle Simulation of Whistler-mode Chorus Emissions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Self-Consistent Particle Simulation of Whistler-mode Chorus Emissions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-Consistent Particle Simulation of Whistler-mode Chorus Emissions will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-973071