Does orbit-averaged theory require a scale separation between periodic orbit size and perturbation correlation length?
نویسندگان
چکیده
Canonical perturbation theory shows that orbit-averaged theory only requires the time-scale separation between equilibrium and perturbed motions and verifies the conventional concept that orbit averaging effects greatly reduce the transport of energetic particles by microturbulence in tokamak. Thereafter, a recent claim [Phys. Rev. Lett. 102, 075004 (2009); 107, 239502 (2011)] of the orbit-averaged theory requiring a scale separation between equilibrium orbit size and perturbation correlation length is erroneous.
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