The steep gradients at the plasma edge in a tokamak result in Edge Localized Modes (ELMs), which when extrapolated to burning plasma conditions, will melt the first wall. In order to reduce the steep gradients to below the instability limit, resonant magnetic perturbation (RMPs), a 3D-field magnetic field perturbation are introduced. RMPs can succesfully suppress or mitigate ELMs through an increase in particle transport. In this presentation, I will first address how RMPs affect the magnetic topology at the plasma edge and whether this change in topology can explain the observed changes in particle transport and confinement. Next, I will discuss, how inadvertently RMPs also increase particle transport in the plasma core, which affect global confinement and the ultimate fusion gain factor.
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