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arXiv · 2603.05003

Reproducing anomalous transport coefficients from electro-static tokamak edge turbulent dynamics

Fabio Moretti·Francesco Cianfrani·Nakia Carlevaro·Giovanni Montani
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Abstract

Turbulent transport near the X-point of a large tokamak is examined using local, gradient-driven simulations that determine the saturated plasma profiles. The distribution of a representative set of particle tracers evolving within these profiles is then analyzed. The study demonstrates that the resulting transport is diffusive, characterized by a coefficient that depends on the spectral properties of the turbulent energy and attains anomalous high values under broad conditions. These findings suggest that anomalous transport is an inherent outcome of the fundamental non-linear drift dynamics of plasmas. The scaling of transport with turbulent energy is also addressed, with implications for future progress toward a mean-field framework for turbulent transport.

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Fabio Moretti, Francesco Cianfrani, Nakia Carlevaro, Giovanni Montani. 2026-03-05. Reproducing anomalous transport coefficients from electro-static tokamak edge turbulent dynamics. https://arxiv.org/abs/2603.05003

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