Electric field induced by radial redistribution of the energetic ion pressure in a fusion plasma

Shaojie Wang

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arXiv · 2601.14834

Electric field induced by radial redistribution of the energetic ion pressure in a fusion plasma

Shaojie Wang

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Abstract

It is found by using the gyrokinetic theory that significant radial electric fields, or zonal flows, can be generated by the radial redistribution of energetic ion pressure in a tokamak fusion device. Trapped energetic ions are more effective to generate the radial electric field than the isotropic energetic ions. This suggests that the energetic $\alpha$ particles produced by DT fusion may induce significant radial electric field and thus help to improve the core plasma confinement in a fusion reactor.

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Shaojie Wang. 2026-01-21. Electric field induced by radial redistribution of the energetic ion pressure in a fusion plasma. https://arxiv.org/abs/2601.14834

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