(TH/P2-12) Thermal Diffusion by Stochastic Electromagnetic Fluctuations

Abstract.  A new simple method has been developed to evaluate the thermal diffusion brought by coexisting homogeneously stochastic electrostatic and electromagnetic fluctuations. This method is significantly useful, because the synergetic treatments of electrons and ions in the electromagnetic gyrokinetic simulations are considered to be quite difficult in the standard experimental situations of LHD and tokamaks. As a most simple case, thermal conductivities for electrons and ions are considered in a large aspect straight tokamak with a small gyro-radius and negligible magnetic shear and negligible equilibrium E×B flow shear. Those analytical formulae applicable to the range beyond so-called quasi-linear limit show that the thermal diffusion of electrons (ions) is mainly dominated by magnetic (electrostatic) fluctuations in the experimentally relevant situations, even if both magnetic and electrostatic fluctuations coexist.

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