MHD stability of negative triangularity DIII-D plasmas

Boyes, W. (ORCID:0000000269304702); Turco, F. (ORCID:0000000237230438); Hanson, J. (ORCID:0000000324324870); Marinoni, A. (ORCID:0000000310045782); Turnbull, A.; Austin, M. (ORCID:0000000200178605); Navratil, G. (ORCID:0000000229305196)

doi:10.1088/1741-4326/acd564

DOE OSTI · 1985944

MHD stability of negative triangularity DIII-D plasmas

Boyes, W. (ORCID:0000000269304702)·Turco, F. (ORCID:0000000237230438)·Hanson, J. (ORCID:0000000324324870)·Marinoni, A. (ORCID:0000000310045782)·Turnbull, A.·Austin, M. (ORCID:0000000200178605)·Navratil, G. (ORCID:0000000229305196)

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Abstract

Abstract Negative triangularity (NT) experiments in DIII-D point to an emergent reactor scenario free of sawteeth, endowed with benign, nondisruptive n = 2 tearing modes, which experience q min ⩾ 1 similar to the positive triangularity hybrid scenario. Plasmas exhibiting this behavior attain β N > 3 , high enough to reconsider long held views of NT stability. Ideal MHD and tearing stability analysis of well-diagnosed equilibrium reconstructions of experimental hybrid-like plasmas predict that among shape parameters, MHD stability limits are only sensitive to average triangularity. Operation is predicted to be possible at β N relevant to upcoming tokamaks and commercial NT reactors.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY MHD Physics negative triangularity scenarios tearing modes

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Boyes, W. (ORCID:0000000269304702), Turco, F. (ORCID:0000000237230438), Hanson, J. (ORCID:0000000324324870), Marinoni, A. (ORCID:0000000310045782), Turnbull, A., Austin, M. (ORCID:0000000200178605), Navratil, G. (ORCID:0000000229305196). 2023-06-20. MHD stability of negative triangularity DIII-D plasmas. https://doi.org/10.1088/1741-4326%2Facd564

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