Fully nonlinear features of the energetic beam-driven instability
- Japan Atomic Energy Agency, Higashi-Ueno 6-9-3, Taitou, Tokyo 110-0015 (Japan)
- Commissariat a l'Energie Atomique, IRFM, F-13108 Saint Paul Lez Durance (France)
The so-called Berk-Breizman model is applied to a cold bulk, weak warm beam, one-dimensional plasma, to investigate the kinetic instability arising from the resonance of a single electrostatic wave with an energetic particle beam. A Vlasov code is developed to solve the initial value problem for the full-f distribution, and the nonlinear evolution is categorized in the whole parameter space as damped, steady-state, periodic, chaotic, or chirping. The saturation level of steady-state solutions and the bifurcation between steady-state and periodic solutions near marginal stability match analytic predictions. The limit of a perturbative numerical approach when the resonant region extends into the bulk is shown. Frequency sweeping is observed, with time-evolution approaching theoretical results. A new method to extract the dissipation rate from frequency diagnostics is proposed. For small collision rates, instabilities are observed in the linearly barely stable region.
- OSTI ID:
- 21282099
- Journal Information:
- Physics of Plasmas, Vol. 16, Issue 9; Other Information: DOI: 10.1063/1.3234249; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
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