Physical picture of collisionless neoclassical polarization current

Past work has introduced that the neoclassical polarization drift of the passing ion is in the same direction as that of the trapped ion. Here, based on the model of single particle motion, our analytical results indicate that the neoclassical polarization drifts of the trapped and passing ions are in the opposite directions without collision considered. This work is helpful to easily understand the previous expression of the collisionless neoclassical polarization current based on the kinetic theories, which is only a small quantity of order O ( e 3 / 2 ) compared to that in the banana collision regime.Past work has introduced that the neoclassical polarization drift of the passing ion is in the same direction as that of the trapped ion. Here, based on the model of single particle motion, our analytical results indicate that the neoclassical polarization drifts of the trapped and passing ions are in the opposite directions without collision considered. This work is helpful to easily understand the previous expression of the collisionless neoclassical polarization current based on the kinetic theories, which is only a small quantity of order O ( e 3 / 2 ) compared to that in the banana collision regime.