Kinetic Simulation Studies of Plasma Measurements and Instabilities in the Polar Ionosphere(1/2)

The earth's ionosphere is a partially ionized plasma system, and its physics may vary with the latitudes. Specifically, the polar ionosphere is a complex system that is directly connected to the interplanetary space and often responds to solar activities due to the magnetic field configuration in the Sun-Earth system. Thus the understanding of the polar ionosphere is crucial in the development of space weather models. To investigate the problems of irregularities and plasma turbulence, the in-situ measurements, such as satellites and sounding rockets, and remote sensing measurements, such as radars and all-sky aurora cameras, have all been widely employed. In the theoretical model, the gradient drift instability and the Kelvin-Helmholtz instability are the primary candidates to be dominant mechanisms for the plasma irregularities and turbulence in the polar ionosphere. The fluid-based theoretical and numerical models have been developed to study the macro-instability processes, but, to understand the evolution from macro-instabilities to the micro-structures of irregularities and plasma turbulences, the development of the kinetic-based simulation models becomes indispensable. The main goals of this research are to use the self-developed kinetic-based models to study the plasma instabilities in the polar ionosphere and to investigate the plasma-instrument or plasma-object interactions in the space environment. The latter study will provide a reference for assessing the performance and future improvements in the in-situ measurements of space and ionospheric plasmas. The developed numerical models can also be directly employed in the design of future spacecraft missions of in-situ plasma measurements in Taiwan.