Nonlinear gyrokinetic Coulomb collision operator
Abstract
A gyrokinetic Coulomb collision operator is derived, which is particularly useful to describe the plasma dynamics at the periphery region of magnetic confinement fusion devices. The derived operator is able to describe collisions occurring in distribution functions arbitrarily far from equilibrium with variations on spatial scales at and below the particle Larmor radius. A multipole expansion of the Rosenbluth potentials is used in order to derive the dependence of the full Coulomb collision operator on the particle gyroangle. The full Coulomb collision operator is then expressed in gyrocentre phasespace coordinates, and a closed formula for its gyroaverage in terms of the moments of the gyrocentre distribution function in a form ready to be numerically implemented is provided. Furthermore, the collision operator is projected onto a HermiteLaguerre velocity space polynomial basis and expansions in the small electrontoion mass ratio are provided.
 Publication:

Journal of Plasma Physics
 Pub Date:
 December 2019
 DOI:
 10.1017/S0022377819000734
 arXiv:
 arXiv:1906.03252
 Bibcode:
 2019JPlPh..85f9004J
 Keywords:

 fusion plasma;
 plasma nonlinear phenomena;
 Physics  Plasma Physics
 EPrint:
 30 pages