Nonlinear nonresonant forces by radio-frequency waves in plasmas

Journal Article · Wed Aug 15 04:00:00 EDT 2007 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2775431· OSTI ID:21072662

Zhe, Gao; Fisch, Nathaniel J; Qin, Hong; Myra, J R ^[1]

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1. Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

Nonresonant forces by applied rf waves in plasmas are analyzed. Along the background dc magnetic field, the force arises from the gradient of the ponderomotive potential. Only when the dc magnetic field is straight, however, is this parallel force completely consistent with that from the single particle picture, where the ponderomotive force depends on the gradients of rf fields only. Across the dc magnetic field, besides the ponderomotive force from the particle picture, additional Reynolds stress and polarization stress contribute to the total force. For waves with frequency much lower than the cyclotron frequency, the perpendicular forces from the particle and fluid pictures can have opposite signs. In plasmas with a symmetry angle (e.g., toroidal systems), nonresonant forces cannot drive net flow or current in the flux surface, but the radial force may influence macroscopic behavior of plasma. Moreover, nonresonant forces may drive flow or current in linear plasmas or in a localized region of toroidal plasmas.

• OSTI ID: 21072662
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 8 Vol. 14; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CYCLOTRON FREQUENCY
ELECTRIC CURRENTS
MAGNETIC FIELDS
MAGNETIC SURFACES
NONLINEAR PROBLEMS
PLASMA
PLASMA CONFINEMENT
POLARIZATION
PONDEROMOTIVE FORCE
POTENTIALS
RADIOWAVE RADIATION
REYNOLDS NUMBER
STRESSES
SYMMETRY