论文信息 - Minimizing chaos during the reconnection process

Minimizing chaos during the reconnection process

Abstract Chaos around the separatrices of resonant chains during the reconnection process in Tokamaks with non-monotonic profiles is analysed. To characterize the extension of chaos in the system, we estimate the convergence of the chaotic lines by computing the winding number profiles in the neighborhood of the separatrices. Some simulations were performed and we have detected, for these non-twist mappings, a reduction of chaos during the reconnection process. A theoretical interpretation based on the overlapping of resonance pictures is proposed in order to explain the decrease of chaos. These results may contribute to interpret the recently observed improvement in reversal magnetic shear in Tokamaks.

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