TRANSPORT PROFILES INDUCED BY RADIALLY LOCALIZED MODES IN A TOKAMAK

A new approach to the calculation of turbulent transport coefficients for radially localized modes is presented. The theory takes into account the nonuniformity of the distribution of rational (resonant) magnetic surfaces in minor radius. This distribution function is proportional to the density of available states of excitation. The resulting density of states correction qualitatively changes the radial profile of the transport coefficients, as compared to the usual local diffusivity formulas. The correction factor calculated for the eta(i)-mode turbulence increases toward the plasma edge and allows a better qualitative agreement of the radial chi(i) profile with experimental data than the conventional approach.