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arXiv · 2512.17337

Influence of plasma shaping on the parity of core-localized toroidal Alfv\'{e}n eigenmode in an advanced tokamak configuration

Shiwei Xue·Ping Zhu·Haolong Li
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Abstract

Toroidal Alfv\'{e}n eigenmodes (TAEs) and energetic particle modes (EPMs) can both be excited by energetic particles from auxiliary heating and fusion-born alpha particles in a tokamak. Using the hybrid kinetic-MHD model implemented in the NIMROD code, the excitation of these modes and their properties are investigated in an advanced tokamak configuration with reversed magnetic shear in the core region. The dominant TAE/EPM is found to exhibit odd parity with an anti-ballooning structure when the plasma has elongated, non-circular two-dimensional shaping. As the plasma shaping becomes more circular with reduced elongation, the mode parity undergoes a transition to even parity accompanied by a ballooning structure. These results may help explain the dominant parity of TAE/EPMs observed in advanced tokamak configurations with different plasma shaping.

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Shiwei Xue, Ping Zhu, Haolong Li. 2025-12-19. Influence of plasma shaping on the parity of core-localized toroidal Alfv\'{e}n eigenmode in an advanced tokamak configuration. https://arxiv.org/abs/2512.17337

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