We consider equalizing times of "longitudinal" and "transverse" electron and ion temperatures of a fully ionized plasma in a uniform magnetic field. For this purpose we use a kinetic equation with such a collision integral that, on one hand, it takes into consideration the strong interaction between particles at small distances and, on the other hand, it takes into consideration the fact that without interaction, plasma, electrons and ions move along helixes. In this sensse such an equation corresponds to the kinetic Boltzmann equation since when calculating relaxation times, there occurs automatically a cutoff for logarithmically diverging integrals at small distances. Consideration of the fact that the trajectories of the non-interacting particles are helixes enables one to discuss a case in which the Larmor radii of the particles are smaller than the Debye radius. It has been shown that under these conditions the role of the maximum impact parameter in a Coulomb logarithm for making the ion temperature isotropic is played by the Larmor radius of the ions, and for making the elecgron temperature isotropic, by the Larmor radius of the electrons.For equalization of the longitudinal and transverse ion temperatures only collisions of ions among one another are important. Electron temperature becomes isotropic through both inter-electron collisions and collisions between electrons and ions. The relaxation times deduced in this work actually determine the pulse relaxation of plasma particles along the magnetic field. Comparison of these expressions with the characteristic times defining the coefficients, obtained earlier, for transfer in a plasma across a magnetic field enables us to say that under conditions such that the field affects the collision process, relaxation times for the pulse along and transverse to the magnetic field differ.
Quasi-linear theory of cherenkov heating of electrons in an inhomogeneous plasma