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DOE OSTI · 2997006

On the formation of edge electric fields in negative triangularity plasmas

Kramer, Gerrit J. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000151058139)·Nelson, Andrew Oakleigh [Columbia Univ., New York, NY (United States)] (ORCID:0000000296121936)·Thome, Kathreen E. [General Atomics, San Diego, CA (United States)] (ORCID:0000000248013922)
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Abstract

The Negative Triangularity (NT) plasma edge is studied with full orbit simulations and compared with similar simulations using a Positive Triangularity (PT) edge geometry. It is found that the thermal edge ions in NT are less well confined than in PT. The edge ion losses in NT set-up an electric field inside the plasma in the loss region. This electric field leads to counter-current edge plasma flows and are consistent with observations in NT plasmas. It could also explain the good edge confinement in NT discharges via the E × B flow shear turbulence suppression mechanism.

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Kramer, Gerrit J. [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000151058139), Nelson, Andrew Oakleigh [Columbia Univ., New York, NY (United States)] (ORCID:0000000296121936), Thome, Kathreen E. [General Atomics, San Diego, CA (United States)] (ORCID:0000000248013922). 2025-10-10. On the formation of edge electric fields in negative triangularity plasmas. https://doi.org/10.1088/1361-6587%2Fae0cfb

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