Bootstrap Current Coefficients in Stellarators
نویسنده
چکیده
A method to derive analytical expressions for bootstrap current coefficients is studied. The drift kinetic equation is divided into two parts corresponding to the effects of local and global structures of magnetic fields. The divided transport coefficients can be approximated by connecting the results of only three types of asymptotic expansions of the divided equations. The current coefficients obtained by adding these two parts approximately reproduce results of a direct numerical calculation of the drift kinetic equation.
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