Physics Topics
What is magnetic self-organization?
Self-organization here refers to the following process. A system is driven such that excess free energy excites instabilities (and possibly turbulence) that cause the system to relax to a lower energy state by rearranging (self-organizing) its large-scale structure. In magnetic self-organization the instabilities are magnetic (the magnetic field fluctuates in space or time); and large-scale quantities that are rearranged include the magnetic field, and possibly other quantities such as flow and pressure. Laboratory plasmas may be driven to a state of high magnetic energy by an applied electric field. Magnetospheric substorms may be driven by the solar wind; solar dynamo and coronal activity may be driven by convection and rotation; magnetic activity in accretion disks may be driven by rotation. The specifications of the drive differ between situations; and in some of the phenomena rearrangement of quantities other than the magnetic field may dominate. But, the phenomena strongly share underlying physics.

What are the major physics questions?
The topics, and sample questions the center will address are as follows (links to research plans are provided):

Dynamos and Flow Driven Magnetic Instabilities
The Madison Plasma Dynamo Experiment
How is kinetic energy in flowing plasma converted to magnetic energy? How does the magnetic field react back on the flow to establish a saturated state? How can hydrodynamically stable flows be destabilized by a magnetic field to generate turbulence, which in turn sustains the magnetic field? How, ultimately, does the turbulent energy dissipate and heat plasma?

Magnetic reconnection
Kinetic simulations of the reconnection layer established in the Magnetic Reconnection Experiment (MRX).
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What is the mechanism that converts magnetic energy into particle kinetic energy? How does reconnection proceed in large systems with emergent structures involving multiple X-lines, plasmoid and flux-rope formation, leading up to turbulence? How does impulsive and rapid reconnection develop in relatively quiescent plasmas? What differentiates reconnection driven by flows, as in high-energy-density (HED) plasmas, from the more conventional magnetically-driven reconnection?

Particle Energization
Observation of fast ions injected by a beam into an MST plasma being accelerated to even higher energy at magnetic reconnection events (depicted by spikes in the magnetic mode amplitude).
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How and when does dissipation of flow and/or magnetic field lead to energization of thermal and non-thermal particles? How do fast particles, such as cosmic rays in astrophysics or high-energy particle beams in the laboratory interact with their environments? How do pressure anisotropies and kinetic effects act back and modify the effectiveness of particle energization and flow self-organization?

Multi-Process and System Integration
Galaxy M87 in radio, showing the jet and lobe structure emanating from a super-massive black hole (at the center). Knotty features along the jet suggest instabilities. Studies from the other research task areas provide physical understanding of individual physical processes, which will be integrated computationally and adapted to disk-jet-lobe geometries and boundary conditions for system modeling.
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Magnetic self-organization requires interaction of multiple physical processes, which operate under a range of geometries, inhomogeneities, and boundary conditions. This cross-cutting thrust will use our comprehensive simulation tools to address energy flow mediated by multiple processes in two different self-organizing systems, one in the laboratory [the MST Reversed Field Pinch], the other astrophysical [the Disk-Jet-Lobe system], in which the three thrust areas dynamos, reconnection and particle energization are coupled, and which provide a platform for interfacing with measurements and observations. Our high-performance computing tools have advanced sufficiently that it is now possible to simulate laboratory experiments with realistic parameters and boundary conditions, enabling the tools to be validated and used for reliable extrapolation to space and astrophysical objects with similar plasma processes. From a unified perspective, these two integrated studies will impact broad questions that have been outstanding in parallel communities for many years, such as ion heating in fusion plasmas as well as the solar corona and wind, and how the lessons learned from studies of transport in magnetized laboratory plasmas can enhance our understanding of the disk-jet-lobe system, and vice versa.