Modulational excitation of drift waves by a beam of lower-hybrid waves
- Equipe Turbulence Plasma, URA A773 CNRS, Institut Mediterraneen de Technologie, F-13451 Marseille Cedex 20 (France)
- Association EURATOM-CEA sur la Fusion, Centre dEtudes de Cadarache, F-13108 Saint Paul lez Durance Cedex (France)
The results of theoretical and experimental studies on excitation of drift waves in a tokamak plasma under the conditions of experiments on lower-hybrid (LH) plasma heating and current drive are presented. It is shown that for sufficiently strong LH pump levels the main effect resulting in the drift wave excitation is the LH wave modulational instability. It is found that the modulational excitation of long-wavelength drift oscillations (with the wavelengths exceeding the length of the LH pump wave) is described by a dispersion equation similar to the equation for the usual hydrodynamical beam instability. This allows us to treat the excitation of the long-wavelength drift waves as modulational excitation by a beam of the LH waves. The theoretical results obtained are compared with the data of the tokamak Tore Supra [{ital Proceedings} {ital of} {ital the} 12{ital th} {ital International} {ital Conference} {ital on} {ital Plasma} {ital Physics} {ital and} {ital Controlled} {ital Nuclear} {ital Fusion}, Nice, 1988 (International Atomic Energy Agency, Vienna, 1989), p. 9] experiment. Qualitative accordance of the theoretical and experimental results is demonstrated. {copyright} {ital 1996 American Institute of Physics.}
- OSTI ID:
- 278489
- Journal Information:
- Physics of Plasmas, Vol. 3, Issue 2; Other Information: PBD: Feb 1996
- Country of Publication:
- United States
- Language:
- English
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