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arXiv · 2409.12329

Analysis of high-field side plasma instabilities in tokamak edge

Maxim V. Umansky
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Abstract

Balanced double-null configurations are of general interest for boundary plasma physics, and they have been proposed for some future designs. Experimental observations demonstrate absence of plasma fluctuations in tokamak high-field side scrape-off layer in a balanced double-null configuration [Smick et al 2013 Nucl. Fusion 53 023001], and it is commonly assumed that plasma instabilities are suppressed on high-field side in the edge plasma due to the stabilizing effect of magnetic curvature. At the same time, the experimental evidence points to extremely steep plasma density profiles on high-field side, which should provide a strong instability drive. In the present study, the drift-resistive-ballooning mode instability model is investigated analytically and numerically to determine the characteristics of plasma instabilities, turbulence, and transport in tokamak scrape-off layer on high-field side.

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Maxim V. Umansky. 2024-09-18. Analysis of high-field side plasma instabilities in tokamak edge. https://arxiv.org/abs/2409.12329

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