Radial current in tokamak during neutral beam injection

Generation of radial current I (r) during the ionization of fast deuterons in their neutral beam injected into a tokamak is considered. The current I (r) and force F determined by the [I (r) x B] product vary in a complicated manner along the tokamak radius. For this reason, the torque that arises together with force F also nonuniformly varies along the radius, which can lead to a shear in the rotation velocity. A sufficiently large magnitude of this shear can result in reduction of both micro- and macroinstabilities in tokamak plasma [1, 2]. The influence of injected beam characteristics and other experimental parameters on the spatial distribution of I (r) in the TUMAN-3M tokamak is considered.