Khatuna Chargazia
Tbilisi State University, Georgia
Title: Recurrent analysis of the large scale structures in non-uniform magnetospheric flows
Biography
Biography: Khatuna Chargazia
Abstract
Near Earth space (ionosphere, magnetosphere) is characterized by complicated dynamics and for modeling of such processes, especially at conditions of external non-stationary impact (bow shock), it is very important for estimation of determined and stochastic parts of the dynamics, as well as the possibility of the generation of large scale wave and fractal structures. In this work, a physical model of the plasma perturbations for experimental data treatment and their physical and theoretical interpretation is obtained. In this model, a nonlinear mechanism of interaction of the perturbations with spatially inhomogeneous space flows is considered. Numerical simulation of formation of such large scale flows are carried out. Time series of velocity flow and magnetic field components of the magnetospheric flows observed by THEMIS satellite mission are studied by virtue of nonlinear methods. For numerical treatment of these data a recurrent diagram method is used, which is effective for short data series. Recurrence is a fundamental feature of the dissipative dynamical systems, which is used for analysis of relaxation processes in the magnetotail. The results of nonlinear analysis of plasma perturbations for interpretation are compared with the signals obtained by Lorentz and Weierstrass function. By virtue of recurrent diagram method, a fractal nature of experimental signals and dynamical chaos parameters. The results of satellite and numerical simulation data are compared.