Evidence for Global Edge–Core Interplay in Fusion Plasmas

Abstract

Large-scale reactor-relevant fusion plasmas are likely to operate near marginal stability. In this regime, we show clear evidence of interplay between core and edge regions of the plasma. This result illustrates aspects of the controversial ‘shortfall problem' in the far-core, near-edge so-called ‘No Man's Land' region and a possible route to resolve this issue. More generally, it emphasises global-scale organisation of turbulence and relevance of edge dynamics to core confinement.