High confinement at low power input in magnetic fusion plasmas: analysis of trade-offs using stability theory

Physics-based conditions are used to unfold trapped or persistent degenerate singularities in a dynamical model for plasma confinement transitions. Structural characterization of the resulting enhanced model achieves unification of previous disparate views of confinement transition physics, provides valuable intelligence on shear flow suppression of turbulence and oscillatory régimes, and suggests targeted experimental design, control and optimization strategies for new-generation fusion experiments. The stability trade-offs involved in achieving high confinement at low power input are discussed.

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