Quasi-coherent fluctuations limiting the pedestal growth on Alcator C-Mod: Experiment and modelling

Diallo, A.; Hughes, J. W.; Baek, S. -G.; LaBombard, Brian; Terry, J.; Cziegler, I.; Hubbard, A.; Davis, E.; Walk, J.; Delgado-Aparicio, L.; Reinke, M. L.; Theiler, C.; Churchhill, R. M.; Edlund, E. M.; Canik, John; Snyder, P.; Greenwald, M.; White, A.

doi:10.1088/0029-5515/55/5/053003

Quasi-coherent fluctuations limiting the pedestal growth on Alcator C-Mod: Experiment and modelling

Journal Article · Thu Apr 09 00:00:00 EDT 2015 · Nuclear Fusion

DOI:https://doi.org/10.1088/0029-5515/55/5/053003· OSTI ID:1265969

Diallo, A. ^[1]; Hughes, J. W. ^[2]; Baek, S. -G. ^[2]; LaBombard, Brian ^[2]; Terry, J. ^[2]; Cziegler, I. ^[3]; Hubbard, A. ^[2]; Davis, E. ^[2]; Walk, J. ^[2]; Delgado-Aparicio, L. ^[1]; Reinke, M. L. ^[2]; Theiler, C. ^[2]; Churchhill, R. M. ^[2]; Edlund, E. M. ^[1]; Canik, John ^[4]; Snyder, P. ^[5]; Greenwald, M. ^[2]; White, A. ^[2]

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Univ. of California, San Diego, CA (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
General Atomics, San Diego, CA (United States)

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. Furthermore, 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.

View Accepted Manuscript (DOE)

Research Organization:: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Organization:: USDOE Office of Science (SC)

Grant/Contract Number:: AC05-00OR22725

OSTI ID:: 1265969

Journal Information:: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 5 Vol. 55; ISSN 0029-5515

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

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