Observation of low frequency electrostatic coherent oscillation in the proximity of the density limit in the TJ-II stellarator. (19th November 2021)

• Record Type: Journal Article
• Authors: Fernández-Ruiz, D.; Losada, U.; Ochando, M.A.; Liu, B.; Hidalgo, C.; the TJ-II Team,
• Is Part Of: Nuclear fusion. Volume 61:Number 12(2021)
• Publication Date: 2021-11-19
• Subjects: zonal flows -- density limit -- stellarators; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/1741-4326/ac3190
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: Turbulence self-regulation mechanisms are widely believed to be partially governed by the non-linear interplay between turbulence and large-scale plasma flows. In this paper, we employ floating potential data recorded via Langmuir probes to study the evolution of long-range correlated structures in plasmas near the operational density limit of the TJ-II stellarator. The results point towards the presence and amplification of low frequency, coherent, global fluctuations with similar properties to those of the zonal flows in the vicinity of this limit.