EXPANSION OF THE RELATIVISTIC FOKKER-PLANCK EQUATION INCLUDING NONLINEAR TERMS AND A NON-MAXWELLIAN BACKGROUND

The relativistic Fokker-Planck collision term in Braams and Karney [Ph ys. Fluids B 1, 1355 (1989)] is expanded using Cartesian tensors (equi valent to associated Legendre spherical harmonics) retaining all non-l inear terms and an arbitrary zeroth order distribution background. Exp ressions are given for collision terms between all harmonics and the b ackground distribution in terms of the j and y functions in Braams and Karney. The results reduce to Braams and Karney for the first order h armonic term with a Maxwellian background and to those given by Shkaro fsky [Can. J. Phys. 41, 1753 (1963)] in the non-relativistic limit. Ex pressions for the energy and momentum transfer associated with relativ istic Coulomb collisions are given. The fast two dimensional Fokker-Pl anck solver in Shoucri and Shkarofsky [Comput. Phys. Commun. 82, 287 ( 1994)] has been extended to include the second order harmonic term. (C ) 1997 American Institute of Physics.