Influence of anomalous particle diffusion on the current system formation and coherence of Pi2 geomagnetic pulsation local ionospheric sources

Abstract

The coherence conditions for local ionospheric sources of Pi2 high-latitude geomagnetic pulsations in the 6–8 mHz frequency band were studied with a method for representing their component spatial distributions by vertical magnetic dipole field integrals over random walk trajectories in the ionospheric horizontal plane. High-quality representations are reached when the field intensity is proportional to a self-intersection density that has spatial and time walk trajectory discontinuities. According to anomalous diffusion theory, the trajectory of the subordinate Levy process is characterized by the stabilization of turning points grouped near pulsation local ionospheric sources. This makes it possible to simulate disturbances of the Pi2 high-latitude pulsation field by a uniform motion along the Hall ionospheric source Levy trajectories with short-term pulsed current switching on-off. A coherent redistribution of the Pi2 local ionospheric source intensity and several observed specific features in the source field distribution dynamics are explained by the independent processes of local field-aligned current formation and intensification-weakening of pulsations caused by the current carrier shift relative to wandering Levy turning points and a stationary observer.