Physics Colloquium with David Hatch

Abstract: The projected size and cost of a fusion power plant is sensitively dependent on plasma confinement.  In most magnetic fusion devices, the confinement is determined by small scale turbulent transport of heat and particles.  This turbulence can be suppressed under certain conditions, dramatically increasing confinement and resulting in transport barriers with enormous gradients of temperature and density over narrow regions of the plasma.  I will also describe theoretical and computational investigations interpreting wide-ranging experimental observations of transport barriers in tokamaks.  This fundamental understanding points to strategies by which transport barriers can be controlled and optimized.  One of the most pressing challenges for magnetic confinement fusion is managing the conflicting demands of heat exhaust and confinement; most conventional strategies for managing the extreme outgoing heat fluxes degrade confinement.  I will introduce a new solution to this conundrum: a divertor concept that works in synergy with transport barriers to enable even greater gains in confinement.  If this can be achieved, it would enable much smaller and cheaper fusion devices than typically envisioned.