This study applies the Hamiltonian method to analyze the nonlinear magnetic topology induced by Resonant Magnetic Perturbations (RMPs) in tokamaks. We investigate the system's chaotic behavior by comparing three methods: the renormalization method, Lyapunov exponents, and weighted Birkhoff average. A strong consistency is found among these methods in predicting the large-scale stochasticity threshold. The magnetic island width threshold provides a quantitative criterion for optimizing RMP-based edge-localized modes control, bridging a critical gap in plasma control strategies.
Gui et al. (Sun,) studied this question.