Fokker-Planck solution for the spherical symmetry of the electron distribution function of a fully ionized plasma

The linearized electron-electron collision operator for the velocity-dependent coefficient of index n=0 in the Legendre expansion in the pitch angle of the electron distribution function of a fully ionized plasma is restated through a redefinition of the dependent variable as an exact differential. Two specific Coulomb loss terms for particles and energy are brought to evidence in the process of transformation to the differential form which are associated with the conserving properties of the collision operator. The inversion of the differential operator can be achieved by simple quadratures. The method is applied to determine the isotropic component of the electron distribution function in velocity space for a number of problems of interest in fusion research.