Kinetic physics of magnetospheric plasma boundaries

Xin An, PhD.

Plasma boundaries are primary sites for mass, momentum, and energy transfer between plasmas of distinct properties. In Earth's magnetosphere, such boundaries include current sheets, fast plasma flows from magnetic reconnection, and the magnetosphere-ionosphere interface. Fundamental kinetic physics governs the dynamics at these boundaries due to strong plasma inhomogeneities and small-scale processes. In this seminar, I will present how thin current sheets in the magnetotail maintain kinetic equilibrium, from both equatorial and low-altitude spacecraft observations. I will then discuss wave modes generated around fast plasma flows and demonstrate how these waves enable energy transfer from meso-scales (>1000 km) to micro-scales (<1 km). Next, I will examine magnetosphere-ionosphere coupling through electron precipitation, showing how subrelativistic electrons are scattered by electromagnetic ion cyclotron waves via nonresonant interactions — providing new insight into a longstanding problem. Finally, I will discuss my long-term vision for studying kinetic physics of boundary layer dynamics, extending from Earth's magnetosphere to moon-plasma interactions and laboratory plasmas.

To participate in this event virtually via Zoom, go to https://uiowa.zoom.us/j/95125000965.