Project RFBR 19-05-00574

Studying informative and energy aspects of the amplitude-frequency modulation of ULF oscillations in the system of solar-terrestrial relations

The fundamental results of the theory of amplitude-frequency modulation have been widely used and are used now in the study of ultra low frequency (ULF) electromagnetic waves of natural origin. There are informative and energy aspects of the physics of modulated oscillations and waves. Amplitude-frequency modulation (AFM) of oscillations contains the most important information about both dynamic processes in the origin of oscillations, which is usually very far from the observer, and the state of the environment on extended propagation paths in space. The development of a methodology for extracting this information is of undoubted interest for the forecast of space weather. The energy aspect consists in studying the power (ponderomotive) and thermal action of modulated ULF waves on cosmic plasma, including the investigation of the wave acceleration of charged particles, as well as the wave mechanisms of generation of electric currents and magnetic fields in cosmic plasma. The aim of the project is to consider possible mechanisms of the AFM for a number of types of ULF oscillations (geomagnetic pulsations) and on this basis to formulate fundamental results concerning the role and place of wave ULF phenomena in the multistage process of energy transfer from the solar wind to the Earth`s magnetosphere and ionosphere. As a result of the project, a classification of modulated signals will be made according to the type of modulation and the types of pulsations, new information will be obtained on the modulation processes of Alfven and ion cyclotron waves propagating in the solar wind and observed on the spacecraft and on the ground in the form of serpentine emission, and other types of ULF electromagnetic phenomena. We will investigate the evolution of ULF wave packets in non-equilibrium medium, analyze the relationship between the amplitude modulation of global geomagnetic pulsations Pc5 and the variations in fluxes of magnetospheric relativistic electrons, study theoretically and experimentally the dispersive spreading of broadband pulses, and give recommendations on the possible practical application of the revealed regularities. At the final stage of the project the results of the research will be summarized in a generalizing review.