On wave-particle interaction in axisymmetric toroidal systems
Artikel i vetenskaplig tidskrift, 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

Författare

Robert Nyqvist

Chalmers, Rymd- och geovetenskap, Icke-linjär elektrodynamik

Mietek Lisak

Chalmers, Rymd- och geovetenskap, Icke-linjär elektrodynamik

J. Zalesny

West Pomeranian University of Technology

Physica Scripta

0031-8949 (ISSN)

Vol. 84 015503- 015503

Fundament

Grundläggande vetenskaper

Ämneskategorier

Annan fysik

DOI

10.1088/0031-8949/84/01/015503