Complete Differential Expansion of the Integral of Elastic Collisions of Electrons with Heavy Neutral Particles

The derivation of the complete differential expansion of the integral of elastic collisions of electrons with heavy neutral particles is performed for the case when the electron distribution function is not symmetric with respect to some direction. The derivation is made under the assumption that the kinetic energy of electrons greatly exceeds the energy of thermal motion of atoms and molecules. It is shown how the resulting expansion can be used to derive equations for the moments of the electron distribution function.