Magnetized plasma kinetic theory. II. Derivation of Rosenbluth potentials for a uniform magnetized plasma

For pt.I see ibid., vol.19, p.237 (1977). It is shown that the kinetic equation for a plasma situated in a magnetic field, of a strength such that the ion Larmor radius is larger than the electron Debye length, has the form of a Fokker Planck equation in which the diffusion and friction coefficients can be derived from 'Rosenbluth potentials' in the usual manner. These 'magnetic Rosenbluth potentials' are however anisotropic, even if the plasma distribution functions is isotropic, because the magnetic field alters the dynamics of ion-electron collisions, and significantly enhances the duration of interaction of ions and electrons with no relative motion parallel to the magnetic field. The potentials are evaluated explicitly in the case of Maxwellian electrons.