Laboratory Studies of Laser-Driven, Ion-Scale Mini-Magnetospheres on the LAPD

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This project will use laboratory experiments to study magnetospheres of cosmic objects. Magnetospheres form when a flowing plasma, like the solar wind, impacts a magnetic obstacle, like a planet, and are an integral part of space weather systems. Earth’s magnetosphere has been observed by spacecraft for decades, but magnetospheres can also exist on much smaller scales, such as around comets or asteroids that are difficult to study directly. This project will create and explore artificial versions of these “mini” magnetospheres in a laboratory environment. By leveraging the ability of the experiments to be carried out with high repeatability, this study will provide an unprecedented, high-resolution three-dimensional map of a dynamic magnetosphere. The results will advance our fundamental understanding of magnetospheres at the smallest scales and, in turn, improve our ability to model planetary, including Earth's, magnetospheres. This project will also provide advanced training and mentorship to graduate students to prepare them for the U.S. STEM workforce.Mini-magnetospheres provide a unique environment to study kinetic-scale plasma physics that have traditionally been modeled with numerical simulations. This project will create ion-scale magnetospheres by coupling a supersonic, laser-driven plasma flow with a dipole magnet embedded in the uniform, magnetized plasma of the Large Plasma Device (LAPD) at the University of California, Los Angeles. High-repetition experiments will produce highly-resolved, volumetric datasets in order to 1) examine the evolution of global magnetospheric structure for a range of dipole magnet and plasma parameters, 2) study the dependence of magnetospheric structure and magnetic reconnection dynamics on the orientation of the dipole field, 3) observe the formation of bow shocks, and 4) compare to 3D particle-in-cell simulations. The results will help validate numerical simulations and magnetospheric models, as well as complement spacecraft observations of mini-magnetospheres such as those associated with comets and lunar magnetic anomalies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.