A turbulent extension of Ohm's law, derived from the self-consistent action-angle transport theory, ispresented. The equation describes the steady-state profile of the current density in axisymmetric magnetized plasmas inthe presence of magnetic turbulence. The hyper-resistive, helicity-conserving contribution, usually derived in theframework of magneto-hydro-dynamics, is recovered, and the hyper-resistivity is defined. Additionally, the generalizedOhm's law contains an anomalous resistivity term, and a term proportional to the current density derivative. For giventhermodynamic profiles, the numerical solution of the equation shows that turbulent contributions, besides regularizingthe current density profile in the central region, lead to an increase of the total plasma current. This ”turbulent bootstrap“effect provides a possible explanation to discrepancies recently observed between experimental current profiles andneoclassical predictions.
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