the effect of a single particle on macroscopic quantities is negligible, the background electromagnetic and flow fields This paper is concerned with the problem of transport in controlled nuclear fusion as it applies to confinement in a tokamak or and their profiles remain fixed. Collisions generate a ranstellarator. Numerical experiments validate a mathematical model dom process, and therefore we study the test particles of Paul R. Garabedian in which the electric potential is determined statistically. Their distribution function satisfies a partial by quasineutrality because of singular perturbation of the Poisson differential equation called the test particle drift kinetic equation. The Monte Carlo method is used to solve a test particle equation. The collision operator is modeled in this equadrift kinetic equation. The collision operator drives the distribution function in velocity space towards the normal distribution, or Max-tion by a second-order elliptic partial differential operator wellian, as suggested by the central limit theorem. The detailed acting in the velocity coordinates, as in a Fokker-Planck structure of the collision operator and the role of conservation of equation. Solutions of the associated diffusion equation in momentum are investigated. Exponential decay of expected values
velocity space decay to the normal distribution, or Maxwelallows the computation of the confinement times of both ions and lian, as suggested by the central limit theorem. In the abelectrons. Three-dimensional perturbations in the electromagnetic sence of the collision operator, the test particle drift kinetic field model the anomalous transport of electrons and simulate the turbulent behavior that is presumably triggered by the displacement equation reduces to a first-order partial differential equacurrent. Comparison with experimental data and derivation of scaltion whose characteristics are the guiding center orbits.
ing laws are presented.