Magnetic reconnection rate during sawtooth crashes in ASDEX Upgrade. (1st July 2022)

• Record Type: Journal Article
• Authors: Samoylov, O.; Igochine, V.; Yu, Q.; Zohm, H.; the ASDEX Upgrade Team,
• Is Part Of: Nuclear fusion. Volume 62:Number 7(2022)
• Publication Date: 2022-07-01
• Subjects: magnetic reconnection -- sawtooth -- tokamak -- MHD; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/1741-4326/ac6617
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: The radial velocity of the plasma core during the sawtooth crashes has been measured for the first time with electron cyclotron emission imaging diagnostic. The measurements have been compared with nonlinear two-fluid simulation. The comparison reveals good qualitative and quantitative agreement, which indicates that two-fluid effects (inertia and pressure gradient of electrons) are sufficient for the correct prediction of the experimental results. Contrarily, the crash time of the Kadomtsev model, which is based on a single-fluid picture of magnetic reconnection, disagrees with the experimental results.