Axisymmetric Tri-Magnetic-Islands Equilibrium of Strongly-Reversed-Shear Tokamak Plasma: An Idea for the Current Hole.

Abstract

The idea of a new equilibrium of a strongly-reversed-shear tokamak plasma with a current hole is proposed. This equilibrium configuration called &ldquo Axisymmetric Tri-Magnetic-Islands (ATMI) equilibrium &rdquo has three islands along the R direction (a central-negative-current island and two side-positive-current islands) and two x-points along the Z direction. The equilibrium is stable with the elongation coils when the current in the ATMI region is limited to be small