Electron Diffusion in a Tokamak Due to High n-Ballooning Mode

抄録

The radial diffusion of electrons due to high-n ballooning modes in a sheared magnetic field of tokamak is investigated. The E×B drift motion of electrons in a fluctuating electric field with many poloidal wave numbers is described by a radial kick. By a Taylor expansion of the safety factor q(r), the equation of motion is reduced to a standard map and the diffusion rate is estimated to be inversely proportional to the parallel velocity. The difference of the diffusion rate due to poloidal electric field fluctuation and radial magnetic field fluctuation is discussed.