FOKKER-PLANCK EQUATION FOR MODERATELY COUPLED PLASMAS

A Fokker-Planck equation has been generalized to treat large-angle as well as small-angle binary collisions in plasmas. For moderately coupled plasmas [2 less than or similar to Coulomb logarithm (lnLAMBDA(b)) less than or similar to 10], calculations have been made of the relaxation rates and transport coefficients. In general they differ from the standard (Braginskii) results by terms of order 1/lnLAMBDA(b). Using a modified collision operator, we obtain a new vector potential that has a direct and practical connection to the Rosenbluth potentials. In addition, we calculate a reduced electron-ion collision operator that, for the first time, manifests 1/lnLAMBDA(b) corrections.