Investigating RMP-Induced Edge Topology in ITER DT-1 Scenarios using EMC3-EIRENE Simulations

The control of Edge-Localized Modes (ELMs) using non-axisymmetric Resonant Magnetic Perturbations (RMPs) is a critical operational requirement for ITER. This research investigates the application of n=3 RMPs to ITER high edge safety factor (high-q) DT-1 scenarios with varying plasma currents and toroidal rotation profiles, focusing on edge magnetic topology and plasma response.

In this initial study, we used the MARS-F code to simulate linear plasma responses to RMPs. Magnetic field lines, including perturbations, were traced into the scrape-off layer and divertor using FLARE. This enables evaluation of edge topology and perturbed field interactions with the plasma boundary, essential for ELM suppression understanding.

Simulations with coil phasing scans revealed a complex, non-monotonic relationship between RMP effects and plasma conditions, particularly toroidal rotation. This underscores the need to consider full plasma states in RMP studies and motivates 3-D modeling. Based on these findings, we conducted EMC3-EIRENE simulations for pure D plasma, analyzing stochastic layer characteristics and divertor heat flux distributions. We compared key quantities like deepest radial incursion and heat flux between high-q DT-1 and SRO scenarios.

These results advance understanding of RMP effectiveness in ITER and highlight the importance of detailed simulations for control strategies. Future work will incorporate realistic transport and impurity conditions to assess impacts thoroughly.