Cross-Analysis of Magnetic and Current Density Field Topologies in a Quiescent High Confinement Mode Tokamak Discharge

In axisymmetric fusion devices like tokamaks, the winding of the magnetic field is characterized by its safety profile q=qB. Similarly, the winding of the current density field is characterized by qJ. Currently, the relationship between qB and qJ profiles and their effect on tokamak plasma confinement properties remains unexplored, as the qJ profile is neither computed nor considered. This study presents a reconstruction of the current density winding profile from experimental data in the quiescent H-mode. The topology analysis derived from (qB,qJ) was carried out using Hamada coordinates. It shows a large central plasma region unaffected by current filamentation-driven resonant magnetic perturbations, while the outer region harbors a spectrum of magnetic resonant modes, induced by current filaments located within the core plasma, which degrade peripheral confinement. These results suggest a QH-mode signature pattern needing further validation with additional data. Implementing (qB,qJ) real-time monitoring could provide insights into tokamak confinement regimes with significant implications.