Field-reversed configuration maintained by rotating magnetic field with high spatial harmonics

Field-reversed configurations ( FRCs) driven by rotating magnetic fields ( RMFs) with spatial high harmonics have been studied in the metal flux conserver of the FRC injection experiment. The experimental results show that the fundamental RMF component is observed to penetrate the plasma column, while the high harmonics are screened at the plasma edge due to their slower or reversed rotation. This selective penetration of the RMF provides good compatibility of radial and azimuthal force balances; significant radial inward force < j(z)B(theta)>> mostly from the high- harmonic components, and sufficient azimuthal torque solely provided by the fundamental component.