Low-noise electromagnetic {delta}f particle-in-cell simulation of electron Bernstein waves

Journal Article · Thu Jun 15 00:00:00 EDT 2006 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2215460· OSTI ID:20787347

Nong, Xiang; Cary, John R; Barnes, Daniel C; Carlsson, John ^[1]

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1. Center for Integrated Plasma Studies, University of Colorado at Boulder, Boulder, Colorado 80309 (United States)

The conversion of the extraordinary (X) mode to an electron Bernstein wave (EBW) is one way to get rf energy into an overdense plasma. Analysis of this is complex, as the EBW is a fully kinetic wave, and so its linear propagation is described by an intractable integro-differential equation. Nonlinear effects cannot be calculated within this rubric at all. Full particle-in-cell (PIC) simulations cannot be used for these analyses, as the noise levels for reasonable simulation parameters are much greater than the typical rf amplitudes. It is shown that the delta-f computations are effective for this analysis. In particular, the accuracy of those computations has been verified by comparison with full PIC, cold plasma theory, and small gyroradius theory. This computational method is then used to analyze mode conversion in different frequency regimes. In particular, reasonable agreement with the theoretical predictions of Ram and Schultz [Phys. Plasmas 7, 4084 (2000)] in the linear regime is found, where 100% X-B mode conversion has been obtained when the driving frequency is less than twice the electron gyrofrequency. The results show that cold-plasma theory well predicts the mode conversion efficiency, as is consistent with the phase-space picture of mode conversion. From this it can be shown that nearly 100% X-B mode conversion cannot be obtained when the frequency is higher than the electron second harmonic cyclotron frequency.

• OSTI ID: 20787347
• Journal Information: Physics of Plasmas, Vol. 13, Issue 6; Other Information: DOI: 10.1063/1.2215460; (c) 2006 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
AMPLITUDES
BERNSTEIN MODE
COLD PLASMA
COMPARATIVE EVALUATIONS
CYCLOTRON FREQUENCY
EFFICIENCY
ELECTROMAGNETIC RADIATION
ELECTRONS
GYROFREQUENCY
HIGH-FREQUENCY HEATING
INTEGRO-DIFFERENTIAL EQUATIONS
MODE CONVERSION
NOISE
NONLINEAR PROBLEMS
PHASE SPACE
PLASMA SIMULATION
PLASMA WAVES
RF SYSTEMS