Theory and observation of electromagnetic ion cyclotron triggered emissions in the magnetosphere

0357117 - ÚFA 2011 RIV US eng J - Journal Article
Omura, Y. - Pickett, J. - Grison, Benjamin - Santolík, Ondřej - Dandouras, I. - Engebretson, M. - Décréau, P. M. E. - Masson, A.
Theory and observation of electromagnetic ion cyclotron triggered emissions in the magnetosphere.
Journal of Geophysical Research. Roč. 115, A7 (2010), A07234/1-A07234/13. ISSN 0148-0227
R&D Projects: GA ČR GAP205/10/2279; GA AV ČR IAA301120601
Institutional research plan: CEZ:AV0Z30420517
Keywords : nonlinear wave growth * EMIC
Subject RIV: BL - Plasma and Gas Discharge Physics
Impact factor: 3.303, year: 2010

We develop a nonlinear wave growth theory of electromagnetic ion cyclotron (EMIC) triggered emissions observed in the inner magnetosphere. We first derive the basic wave equations from Maxwell's equations and the momentum equations for the electrons and ions. We then obtain equations that describe the nonlinear dynamics of resonant protons interacting with an EMIC wave. The frequency sweep rate of the wave plays an important role in forming the resonant current that controls the wave growth. Assuming an optimum condition for the maximum growth rate as an absolute instability at the magnetic equator and a self-sustaining growth condition for the wave propagating from the magnetic equator, we obtain a set of ordinary differential equations that describe the nonlinear evolution of a rising tone emission generated at the magnetic equator.
Permanent Link: http://hdl.handle.net/11104/0195462