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Cross-scale interaction between microturbulence and fishbone in fusion plasmas

Yuehao Ma1, Bin Zhang2, Liutian Gao1, Pengfei Liu3, Jian Bao3, Zhihong Lin4, Huishan Cai1,*, AhDi Liu1, Hailin Zhao2 et al.

Tao Zhang2

  • *Contact author: hscai@mail.ustc.edu.cn
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Phys. Rev. Research 8, 033092 – Published 22 July, 2026

DOI: https://doi.org/10.1103/h216-w3nq

Abstract

Global gyrokinetic simulations are performed for the first time to investigate cross-scale interactions between electromagnetic ion temperature gradient (ITG) turbulence and fishbone instability in tokamak plasmas. The investigation of fluctuation response in the multiscale simulation including both instabilities indicates a strong impact of fishbone on ITG turbulence. Detailed analysis reveals that fishbone-driven zonal radial electric fields at nonlinear saturation significantly suppress electromagnetic ITG turbulence, reducing ion thermal transport close to the neoclassical level. The simulation results agree well with experimental observations of turbulence suppression during fishbone bursts. These findings advance understanding of multiscale interactions that enhance thermal confinement in fusion plasmas.

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Phys. Rev. Research 8, 033092– Published 22 July, 2026
  • Received 6 November 2025
  • Accepted 1 July 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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