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arXiv · 2512.18394

Nondiffusive transport of inertial heavy impurities in drift-wave turbulence

Zetao Lin·Benjamin Kadoch·Sadruddin Benkadda·Kai Schneider
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Abstract

We investigate the transport behavior of tungsten impurities with finite inertia in drift-wave turbulence using the Hasegawa-Wakatani model. Unlike previous tracer-based models, our simulations reveal a transition to non-diffusive dynamics for a range of charge states. This novel mechanism offers a turbulence-driven route to core impurity accumulation. This finding underscores the nontrivial role of particle inertia in impurity dynamics and has strong implications for impurity control in future fusion devices.

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Zetao Lin, Benjamin Kadoch, Sadruddin Benkadda, Kai Schneider. 2025-12-20. Nondiffusive transport of inertial heavy impurities in drift-wave turbulence. https://doi.org/10.1103/4px7-2vtt

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