Transport of parallel momentum induced by current-symmetry breaking in toroidal plasmas.
The symmetry of a physical system strongly impacts on its properties. In toroidal plasmas, the symmetry along a magnetic field line usually constrains the radial flux of parallel momentum to zero in the absence of background flows. By breaking the up-down symmetry of the toroidal currents, this constraint can be relaxed. The parallel asymmetry in the magnetic configuration then leads to an incomplete cancellation of the turbulent momentum flux across a flux surface. The magnitude of the subsequent toroidal rotation increases with the up-down asymmetry and its sign depends on the direction of the toroidal magnetic field and plasma current. Such a mechanism offers new insights in the interpretation and control of the intrinsic toroidal rotation in present day experiments.
Camenen
Y
Y
Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
Peeters
A G
AG
Angioni
C
C
Casson
F J
FJ
Hornsby
W A
WA
Snodin
A P
AP
Strintzi
D
D