Radial transport of toroidal angular momentum in tokamaks

The radial flux of toroidal angular momentum is needed to determine tokamak intrinsic rotation profiles. Its computation requires knowledge of the gyrokinetic distribution functions and turbulent electrostatic potential to second-order in $\epsilon = \rho/L$, where $\rho$ is the ion Larmor radius and $L$ is the variation length of the magnetic field. In this article, a complete set of equations to calculate the radial transport of toroidal angular momentum in any tokamak is presented. In particular, the $O(\epsilon^2)$ equations for the turbulent components of the distribution functions and electrostatic potential are given for the first time without assuming that the poloidal magnetic field over the magnetic field strength is small.

Comments: 39 pages. Version to be published in Plasma Physics and Controlled Fusion

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Affiliations: 1Max-Planck-Institut für Plasmaphysik, 2Department of Physics, Chalmers University of Technology, 3Max-Planck-Institut für Plasmaphysik, 4Max-Planck-Institut für Plasmaphysik

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