Cheremnykh S. Investigation of sporadic and ultra low-frequency processes in the inner magnetosphere of the Earth

The thesis is devoted to the study of ultra low-frequency and sporadic processes in the inner magnetosphere of the Earth. System of equations was obtained for arbitrary small oscillations of ULF waves in the dipole magnetic field within the single-fluid ideal MHD. It was found that the exact solution of the resulting system of equations is toroidal Alfven modes and poloidal Alfven modes linked with the slow magnetosonic modes. These solutions are implemented in the near-Earth plasma in the form of eigenmodes due to the interaction of the solar wind with the Earth's magnetosphere. Set damping effect for toroidal Alfven waves because mixing phase perturbations. It is shown that a separate branch of magnetosonic modes and small-scale-cross modes with "mixed" polarization in the Earth's magnetosphere are not implemented. The motion in the plasma flow force-free magnetic configurations of a cylindrical tube, compressed ellipsoid and the toroid, was analyzed in view of the medium inside and outside of these structures. It is found that the movement of these structures is consistent with the movement of the solar wind. It is noted that these structures contains the southern component of the magnetic field and, therefore, can generate geomagnetic storms. A numerical bilinear model of behavior of Dst-index in time was built. It characterizes the sporadic change of the magnetic field, which gives reasonable forecast for 5-6 hours and can be used to predict the geomagnetic storms. The approach to predicting the behavior of Dst-index using local Lyapunov exponents was proposed. Procedure was implemented for calculating the forecast horizon Dst-index time behavior.