The role of turbulent separatrix tangle in the improvement of the integrated pedestal/heat exhaust issue for stationary operation in ITER and Fusion Reactors

We find a different type of homoclinic tangles that are driven by stationary electromagnetic turbulence in the edge of diverted tokamak plasma and that are different from those driven by external RMP coils or transient ELMs. This new finding could shed light on the anomalous nonlocal-transport coupling seen in the present experiments between the edge pedestal and divertor plasma in high-beta tokamak plasmas, and could be an important factor in the ITER operation scenario development in optimizing the integrated performance between plasma confinement and divertor heat-load width. This new finding could also shed light on optimizing utilization of the X-point radiation by light impurity seeding (such as Ne) in ITER. Validation of this new theoretical/computational finding on existing tokamaks and possible control of the EM-turbulence driven homoclinic tangle amplitude by using a divertor-integrated RF antenna in ITER and FPP will also be suggested.