Turbulence-induced safety factor profile flattening at rational surfaces in tokamaks with low magnetic shear
Year: 2025
Type: article
Abstract: In this paper, we investigate the effects of ion-scale turbulence-generated currents on the local safety factor profile under conditions of low magnetic shear and proximity to rational surfaces, relevant to internal transport barrier formation. Our results show that turbulent currents can generate stationary zonal magnetic potential corrugations, producing a stepped safety factor profile with extended regions of zero magnetic shear. This change significantly affects turbulence self-interaction, resulting in a substantial decrease in turbulent transport, indicating a potential triggering mechanism for transport barrier formation.
Authors: Arnas Volčokas, Justin Ball, Giovanni Di Giannatale, Stephan Brunner
Institution: École Polytechnique Fédérale de Lausanne
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,325
Funders: National Science Foundation, EUROfusion, European Commission, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Centro Svizzero di Calcolo Scientifico, National Supercomputing Centre Singapore, Euratom Research and Training Programme, Staatssekretariat für Bildung, Forschung und Innovation
OpenAlex ID: W7114898995