On wave-particle interaction in axisymmetric toroidal systems
Journal article, 2011

A general formalism is developed to describe the interaction of charged particles with electromagnetic waves in terms of coupled finite difference mapping equations that incorporate tokamak topology. The approach is based on considering non-adiabatic changes in the constants of particle motion and it covers a range of wave-particle resonance frequencies, from the precessional to cyclotron frequencies of both passing and trapped ions. The concept of overlapping resonances is used to estimate the threshold for a single plane wave to cause stochastic particle motion. In the stochastic regime, the process is Markovian, and particle diffusion in three-dimensional phase space takes place. Estimations of diffusion coefficients are carried out in the two cases of waves interacting with passing and trapped ions by means of the cyclotron and bounce resonances, respectively, and previously known results are recovered in the proper limits.

instability

lower hybrid wave

rf field

tokamaks

oscillations

electrostatic wave

cyclotron-resonance

stochastic acceleration

motion

plasma

Author

Robert Nyqvist

Chalmers, Earth and Space Sciences, Nonlinear electrodynamics

Mietek Lisak

Chalmers, Earth and Space Sciences, Nonlinear electrodynamics

J. Zalesny

West Pomeranian University of Technology

Physica Scripta

00318949 (ISSN) 14024896 (eISSN)

Vol. 84 1 015503- 015503

Roots

Basic sciences

Subject Categories

Other Physics Topics

DOI

10.1088/0031-8949/84/01/015503

More information

Created

10/8/2017