Nonlinear cyclotron-resonance accelerations by a generalized EM wave

Kazuhiro Akimoto (1) , Hitoshi Hojo (2)

1 DEPARTMENT OF ELECTRICAL ENGINEERING - School of Science and Engineering
2 CENTER FOR PLASMA RESEARCH - Department of Physics

Particle accelerations by a 1D, EM, dispersive pulse in an external magnetic field are investigated. It is found that the well-known cyclotron resonance may be classified into three regimes as the length and/or the amplitude of the pulse are varied. Namely, as the pulse amplitude increases, the transit-time cyclotron-resonance acceleration [CRA] evolves to phase trapping, and reflect particles. The amplitude and wave dispersion as well as the pulse length strongly affect those accelerations. The interesting phenomena of quantization of resonance velocities in between the two regimes are also investigated. This new mechanism may lead to wave amplification at some discrete frequencies other than the cyclotron frequency.

Mots clés: Cyclotron-resonance; bifurcation; acceleration; quantization; electromagnetic waves

Domaines: Physique des plasmas [physics.plasm-ph]

Kazuhiro Akimoto, Hitoshi Hojo. Nonlinear cyclotron-resonance accelerations by a generalized EM wave. 2004. ⟨hal-00001744⟩