Relativistic electron beam acceleration by nonlinear scattering of electromagnetic waves in a magnetized plasma

Journal Article · Tue Jan 15 00:00:00 EST 2008 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2825000· OSTI ID:21069974

Sugaya, R ^[1]

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1. Department of Physics, Faculty of Science, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

Acceleration and heating of a relativistic electron beam due to nonlinear electron Landau and cyclotron damping of electromagnetic waves in a magnetized plasma are investigated theoretically and numerically on the basis of the relativistic kinetic wave and transport equations derived from the relativistic Vlasov-Maxwell equations. Two electromagnetic waves interact nonlinearly with the relativistic electron beam, satisfying the resonance condition of {omega}{sub k}-{omega}{sub k{sup '}}-(k{sub perpendicular}-k{sub perpendicula=} r{sup '})v{sub d}-(k{sub parallel}-k{sub parallel}{sup '})v{sub b}{approx_equal}m{omega}{sub ce}, where v{sub b} and v{sub d} are the parallel and perpendicular velocities of the relativistic electron beam, respectively, and {omega}{sub ce} is the relativistic electron cyclotron frequency for the electron beam. The beat waves whose frequency is near the frequency of the extraordinary wave are excited by two electromagnetic waves. The beat waves resonate with the relativistic electron beam and accelerate efficiently. Nonlinear electron Landau and cyclotron damping of the electromagnetic waves has been studied by the numerical analysis of the relativistic nonlinear wave-particle coupling coefficients, assuming the relativistic electron beam with the relativistic drifted Maxwellian momentum distribution without the cross-field drift (v{sub d}=0), and it was verified that the highly relativistic electron beam with the energy of {beta}m{sub e}c{sup 2} < or approx. 5 TeV can be accelerated efficiently by the Compton scattering and the beat-wave excited extraordinary waves, where {beta}=(1-v{sub b}{sup 2}/c{sup 2}){sup -1/2}. For comparison, the equations of motion for the beam electrons trapped in the beat wave in the frame of reference moving with v{sub b} are analyzed. The detailed acceleration mechanism was clarified and the qualitative agreement with the numerical results was obtained.

• OSTI ID: 21069974
• Journal Information: Physics of Plasmas, Vol. 15, Issue 1; Other Information: DOI: 10.1063/1.2825000; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAM-PLASMA SYSTEMS
BOLTZMANN-VLASOV EQUATION
COMPARATIVE EVALUATIONS
COMPTON EFFECT
CYCLOTRON FREQUENCY
DAMPING
ELECTROMAGNETIC RADIATION
ELECTRON BEAMS
ELECTRONS
EQUATIONS OF MOTION
MAXWELL EQUATIONS
NONLINEAR PROBLEMS
NUMERICAL ANALYSIS
PLASMA ACCELERATION
PLASMA GUNS
RELATIVISTIC PLASMA
RELATIVISTIC RANGE
TEV RANGE
TRANSPORT THEORY