Simulation study of Bernstein modes

Journal Article · Sat Jul 01 04:00:00 EDT 1978 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.862354· OSTI ID:7051287

Kamimura, T; Wagner, T; Dawson, J M

The properties of Bernstein modes were investigated through computer simulations using two-dimensional and two-and-one-half-dimensional (i.e., two spatial and three velocity coordinates) electrostatic models with fixed magnetic field. The measured discrete spectrum was found to agree with the linear dispersion relation for these modes. The quasi-periodic phenomenon of early phase-mixing damping and later recurrence, predicted by Baldwin and Rowlands, was observed. For large wavenumber k/sub perpendicular/, the initial damping rate is the same as that for Landau damping in an unmagnetized plasma; for small k/sub perpendicular/, however, it is much stronger. The recurrence peaks slowly damp in time at a rate proportional to k/sup 2//sub perpendicular/D, where D is the measured cross-field particle diffusion coefficient which is dominated by convective transport. Finally, splitting of the main spectral peaks and the appearance of subpeaks at half-integral multiples of the cyclotron frequency are observed and may be explained by nonlinear mode coupling.

• Research Organization: Department of Physics, University of California, Los Angeles, California 90024
• OSTI ID: 7051287
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 21:7; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700108* -- Fusion Energy-- Plasma Research-- Wave Phenomena
BERNSTEIN MODE
CORRELATION FUNCTIONS
CYCLOTRON HARMONICS
DAMPING
DIFFUSION
DISPERSION RELATIONS
EQUILIBRIUM PLASMA
FUNCTIONS
HARMONICS
LANDAU DAMPING
MAGNETIC FIELDS
OSCILLATION MODES
OSCILLATIONS
PLASMA
PLASMA SIMULATION