Observation of toroidal flow antiparallel to the <E(r) x B(straight theta)> drift direction in the hot electron mode plasmas in the compact helical system

Phys Rev Lett. 2001 Apr 2;86(14):3040-3. doi: 10.1103/PhysRevLett.86.3040.

Abstract

A toroidal flow antiparallel to the <E(r) x B(straight theta)> drift direction is observed in the hot electron mode plasmas when a large positive electric field and a sharp electron temperature gradient are sustained inside the internal transport barrier in the Compact Helical System. This toroidal flow reaches up to 5x10(4) m/s at the plasma center, and it is large enough to reverse the toroidal flow driven by a tangentially injected neutral beam. These observations clearly show the plasma favors flow in the minimum nablaB direction at the transport barrier.