Quasi-Coherent Fluctuations Limiting the Pedestal Growth on Alcator C-Mod: Experiment and Modeling

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.

doi:10.7910/DVN/1KHJ9H

Title: Quasi-Coherent Fluctuations Limiting the Pedestal Growth on Alcator C-Mod: Experiment and Modeling

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Abstract

Performance predictions for future fusion devices rely on an accurate model of the pedestal structure. The leading 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 (KBM). This work extends recent work on Alcator C-Mod [Diallo, et al., Phys. Rev. Lett., , (2014), 115001], to include detailed measurements of the edge fluctuations and comparisons of edge simulation codes and experimental observations.

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.

OSTI

Publication Date:: Tue Mar 16 00:00:00 EDT 2021

DOE Contract Number:: FC02-99ER54512; AC02-09CH11466

Research Org.:: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Collaborations:: Alcator C-Mod Team

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

OSTI Identifier:: 1881839

DOI:: https://doi.org/10.7910/DVN/1KHJ9H

Citation Formats


                    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., and White, A. Quasi-Coherent Fluctuations Limiting the Pedestal Growth on Alcator C-Mod: Experiment and Modeling.  United States: N. p., 2021. 
        Web.  doi:10.7910/DVN/1KHJ9H.

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                    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. Quasi-Coherent Fluctuations Limiting the Pedestal Growth on Alcator C-Mod: Experiment and Modeling.  United States.  doi:https://doi.org/10.7910/DVN/1KHJ9H

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                    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., and White, A. 2021.  
"Quasi-Coherent Fluctuations Limiting the Pedestal Growth on Alcator C-Mod: Experiment and Modeling".  United States.  doi:https://doi.org/10.7910/DVN/1KHJ9H.  https://www.osti.gov/servlets/purl/1881839. Pub date:Tue Mar 16 00:00:00 EDT 2021

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@article{osti_1881839,

  title        = {Quasi-Coherent Fluctuations Limiting the Pedestal Growth on Alcator C-Mod: Experiment and Modeling},

  author       = {Diallo, A. and Hughes, J. W. and Baek, S-G. and LaBombard, B. and Terry, J. and Cziegler, I. and Hubbard, A. and Davis, E. and Walk, J. and Delgado-Aparicio, L. and Reinke, M. L. and Theiler, C. and Churchill, R. M. and Edlund, E. M. and Canik, J. and Snyder, P. and Greenwald, M. and White, A.},

  abstractNote = {Performance predictions for future fusion devices rely on an accurate model of the pedestal structure. The leading 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 (KBM). This work extends recent work on Alcator C-Mod [Diallo, et al., Phys. Rev. Lett., , (2014), 115001], to include detailed measurements of the edge fluctuations and comparisons of edge simulation codes and experimental observations.},

  doi          = {10.7910/DVN/1KHJ9H},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Mar 16 00:00:00 EDT 2021},

  month        = {Tue Mar 16 00:00:00 EDT 2021}

}

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DOI: https://doi.org/10.7910/DVN/1KHJ9H

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