Plasma parameter scaling of the error-field penetration threshold in tokamaks

A previously published analytical formula for the error-field penetration threshold in rotating tokamak plasmas is successfully benchmarked against nonlinear magnetohydrodynamical simulations in slab geometry. Moreover, the fundamental assumption underlying the derivation of this formula, namely, that the response of a flowing plasma to a low amplitude, quasistatic, resonant magnetic perturbation is governed by linear, constant-psi layer physics, is verified over a wide range of plasma parameters, which includes the parameter range relevant to Ohmic and neutral beam injection start-up discharges in modern-day tokamaks. It is concluded that the formula in question can be used to estimate error-field penetration thresholds in such plasmas. (C) 2003 American Institute of Physics.