The mechanism of collisionless transformation of the orbits of trapped and localized particles as a result of toroidal drift is studied. The probabilities of such a transformation are calculated. The plasma regions in which this mechanism leads to the formation of qualitatively different orbits are determined. A method for a kinetic description of the effects associated with the transformation is proposed. Localized particle transport in situations where the collision frequency is low is discussed. Expressions are obtained for fluxes of localized particles in the internal region of the plasma in which closed orbits are formed.
Neoclassical theory of collisional transport in the presence of fusion α-particles