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arXiv · 1304.3633

Intrinsic rotation driven by non-Maxwellian equilibria in tokamak plasmas

M. Barnes·F. I. Parra·J. P. Lee·E. A. Belli·M. F. F. Nave·A. E. White
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Abstract

The effect of small deviations from a Maxwellian equilibrium on turbulent momentum transport in tokamak plasmas is considered. These non-Maxwellian features, arising from diamagnetic effects, introduce a strong dependence of the radial flux of co-current toroidal angular momentum on collisionality: As the plasma goes from nearly collisionless to weakly collisional, the flux reverses direction from radially inward to outward. This indicates a collisionality-dependent transition from peaked to hollow rotation profiles, consistent with experimental observations of intrinsic rotation.

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M. Barnes, F. I. Parra, J. P. Lee, E. A. Belli, M. F. F. Nave, A. E. White. 2013-04-12. Intrinsic rotation driven by non-Maxwellian equilibria in tokamak plasmas. https://doi.org/10.1103/physrevlett.111.055005

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