Quasi-coherent fluctuations limiting the pedestal growth on Alcator C-Mod: experiment and modelling. (9th April 2015)

• Record Type: Journal Article
• Authors: Diallo, A.; Hughes, J.W.; Baek, S-G.; LaBombard, B.; Terry, J.; Cziegler, I.; Hubbard, A.; Davis, E.; Walk, J.; Delgado-Aparicio, L.; Reinke, M.L.; Theiler, C.; Churchill, R.M.; Edlund, E.M.; Canik, J.; Snyder, P.; Greenwald, M.; White, A.
• Other Names: collab.
• Is Part Of: Nuclear fusion. Volume 55:Number 5(2015:May)
• Publication Date: 2015-04-09
• Subjects: ELM physics -- H-Mode -- tokamaks -- edge turbulence -- kinetic ballooning mode -- MHD instabilities -- microinstabilities; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/0029-5515/55/5/053003
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: Performance predictions for future fusion devices rely on an accurate model of the pedestal structure. The candidate for predictive pedestal structure is EPED, and it is imperative to test the underlying hypotheses to further gain confidence for ITER projections. Here, we present experimental work testing one of the EPED hypotheses, namely the existence of a soft limit set by microinstabilities such as the kinetic ballooning mode. This work extends recent work on Alactor C-Mod (Diallo et al 2014 Phys. Rev. Lett. 112 115001 ), to include detailed measurements of the edge fluctuations and comparisons of edge simulation codes and experimental observations.