Possibility of Poloidal Current Drive by Low Energy Axial NBI into Field-Reversed Configuration Plasma

Abstract

Possibility of the poloidal current drive by low energy axial neutral beam injection is studied by a Monte-Carlo method for field-reversed configuration (FRC) plasma. In order to suppress the end-loss rate of beam ions, it is found that the separatrix beta of target plasma should be low (presumably less than 0.1). If a beam source of a few 100 eV can be developed, beam ions could be trapped inside the separatrix and poloidal current drive would be possible even for FRC plasma embedded in the open-field region.