Current production by cyclotron heating of electrons passing through an axial magnetic field gradient

A steady-state current can be produced in a toroidal plasma by absorption of an electron cyclotron heating wave in the region of a localized magnetic field gradient along the magnetic field lines. The current produced by this mechanism flows in the same direction as the Fisch-Boozer current and it is equivalent in magnitude for reasonable values of ΔB/B. The scaling of the ratio current to RF power absorbed with the plasma variables n, T, and R (major radius), is the same for both currents, namely T/nR.