Understanding Turbulent Mixing in Laboratory Magnetospheres

Plasmas constitute over 99% of the visible universe and turbulent mixing of plasmas is a fundamental process that is important both in natural and artificial situations. Turbulent mixing of ionized gas, called plasma, is especially fascinating when the plasma is embedded inside a strong magnetic force field. Mixing of magnetized plasma has special geometric relationships, couples energy from small and large sized vortex-like structures know as "eddies," and creates self-organization through a remarkable turbulent "pinch." A collaboration between two universities will operate two unique facilities, called laboratory magnetospheres, that contain high-temperature ionized gas using a magnetic force field that resembles the field that surround our Earth and other planets. New measurements will be combined with new theories and simulations that will answer unresolved questions including: How do plasma eddies couple energy at different sizes? How do plasmas evolve during turbulent mixing? What mechanisms cause turbulent self-organization? New science will advance including: (1) global imaging and control of turbulent interchange mixing in a variety of plasma conditions, (2) study of electrostatic self-organization through the understanding of the turbulent pinch, and (3) validating our models for lowfrequency turbulence by carrying out self-consistent nonlinear simulations of turbulent mixing in laboratory magnetospheres.

This research has broad impact because turbulent mixing of magnetized plasma is ubiquitous and fundamental. Understanding turbulent mixing in laboratory magnetospheres will improve our understanding of (1) processes occurring in the ionosphere, which is important to satellite communication, (2) turbulence inside the central regions of planetary magnetospheres, which is important to space weather models, and (3) the anisotropic mixing of low-dimensional fluid systems, which is important to industrial processes. Additionally, this collaborative research uses state-of-the-art facilities at highly-regarded research universities to motivate students and scientists to explore plasma dynamics in a magnetic configuration that resembles a magnetosphere and to encourage the next generation of scientists able to understand and control high-temperature, ionized matter.