Description:
<jats:title>Abstract</jats:title>
<jats:p>The nonlinear interaction between the <jats:inline-formula>
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</jats:inline-formula> beta-induced Alfvén eigenmode (BAE) and the <jats:inline-formula>
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</jats:inline-formula> tearing mode (TM) observed in the HL-2A experiment is systematically studied with the hybrid kinetic-magnetohydrodynamic code M3D-K. It is found that the nonlinear growth of TM can lead to a gradient buildup on the magnetic island (MI) edge, and then triggers the destabilization of the linearly-stable BAE. Then, the triggered BAE together with TM can produce a significant redistribution of energetic particles. For BAE linearly-dominant-unstable case, the TM activity results in the inward motion of BAE mode structure, and the BAE can have a delay effect on the MI saturation. Furthermore, a high-frequency axisymmetric <jats:inline-formula>
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</jats:inline-formula> ‘breathing’ mode is generated by the mode coupling of BAE and TM, agreeing well with the experimental observation, and causes the synchronized periodic oscillation of MI width.</jats:p>