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Abstract: Much of the plasma that fills the heliosphere is in a state of turbulence, where the energy associated with large-scale flows and fields is transferred to smaller and smaller scales until it is dissipated into thermal degrees of freedom. This dissipation must be mediated through plasma processes, as collisions are too infrequent to effectively heat ions and electrons throughout the corona, the solar wind, and Earth’s magnetosheath. While many processes may be responsible for turbulent heating and dissipation, one potentially significant mechanism is magnetic reconnection, a process that converts magnetic energy into bulk flow and heating. In this seminar, I will present results on the interplay between turbulence and magnetic reconnection from a kinetic perspective. Results are presented from Particle-in-Cell turbulence simulations and in-situ observations of the magnetosheath made with the Magnetospheric Multiscale mission. Magnetic reconnection is found to be ubiquitous throughout turbulence and to dissipate magnetic energy in a manner statistically consistent with “fast” reconnection. However, it is also found that the complexity of plasma turbulence leads to a range of reconnection regimes that were previously under-studied or unexplored, including “electron-only” reconnection and shear-flow modified reconnection. These works show that reconnection remains a promising candidate for collisionless heating in plasma turbulence and helps to further our understanding of anomalous heating observed throughout the solar wind and magnetosphere.

Hosted by Professor Yi-Hsin Liu

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https://dartmouth.zoom.us/j/94966101884?pwd=TVZ0V0gxZmdhNnZBcmJieHI5bGo5dz09

Meeting ID: 949 6610 1884
Email physics.department@dartmouth.edu for passcode