COSMIC-RAY KINETICS IN A RANDOM ANISOTROPIC REFLECTIVE NONINVARIANT MAGNETIC-FIELD

The problem of high-energy charged particle propagation in a turbulent medium with a "frozen-in" statistically anisotropic reflective non-invariant magnetic field attracts much attention at the present time. We show that the existence of a large-scale electric field, of which the value is determined by a magnetic helicity, leads to the appearance of an effective mechanism of particle acceleration. We derive the kinetic equation for the particle distribution function and calculate its diffusion approximation. An analysis of the effectiveness of acceleration mechanisms in the observed spectrum of cosmic rays shows that the newly considered mechanism dominates over the second-order Fermi particle acceleration in the energy range of up to 1 GeV.