Plasma Response to Applied Resonant Magnetic Perturbations in DIII-D

Sandia National Laboratories, Albuquerque, New Mexico, USA Resonant magnetic perturbations (RMPs) have been applied to tokamak plasmas as a means of controlling [1] edge localized modes (ELMs), in an effort to mitigate the deleterious effects of these impulsive heat loads on future tokamak devices [2]. In DIII-D, the application of n=3 RMP fields induces a reduction in the edge pressure gradients [3,4] thereby suppressing Peeling-Ballooning modes [5] and therefore, ELMs [6]. On the other hand, ELM mitigation was achieved in JET with a n=1 RMP field that resulted in reduced ELM size and increased ELM frequency [7]. Application of a n=3 RMP in DIII-D reduces the edge pressure gradient by lowering the electron density, n