Stellarator and tokamak plasmas: a comparison

  title={Stellarator and tokamak plasmas: a comparison},
  author={Per Helander and C. D. Beidler and Thomas Bird and Michael Drevlak and Y. Feng and Roman Hatzky and Frank Jenko and Ralf Kleiber and Josefine H E Proll and Y Turkin and Pavlos Xanthopoulos},
  journal={Plasma Physics and Controlled Fusion},
An overview is given of physics differences between stellarators and tokamaks, including magnetohydrodynamic equilibrium, stability, fast-ion physics, plasma rotation, neoclassical and turbulent transport and edge physics. Regarding microinstabilities, it is shown that the ordinary, collisionless trapped-electron mode is stable in large parts of parameter space in stellarators that have been designed so that the parallel adiabatic invariant decreases with radius. Also, the first global… 

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