Stabilization of Toroidal Currents in High-βPlasmas by Surface Magnetic Fields

Abstract

Without the imposition of a toroidal magnetic field, a toroidal plasma current is sustained whose maximum current density increases linearly with the applied poloidal surface magnetic field strength. Both plasma compression and heating are observed in the main weak-field region, and average ..beta.. approx. = 6% and energy confinement time tau = 1 msec have been achieved. This concept significantly increases the ..beta.. values and the allowable current in toroidal, Ohmically heating plasmas.