Behavior of geodesic acoustic mode and limit-cycle oscillation approaching L-H transition in JFT-2M tokamak. (1st November 2022)

• Record Type: Journal Article
• Authors: Kobayashi, T; Sasaki, M; Ido, T; Kamiya, K; Miura, Y; Ida, K; Itoh, K
• Is Part Of: Plasma physics and controlled fusion. Volume 64:Number 11(2022)
• Publication Date: 2022-11-01
• Subjects: L-H transition -- geodesic acoustic mode -- limit-cycle oscillation -- turbulence; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/1361-6587/ac9333
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: In this paper, a phenomenology of competing behavior between the geodesic acoustic mode (GAM) and the limit-cycle oscillation (LCO) is presented. Before the LCO occurs, the GAM can grow to the observable amplitude via the turbulent Reynolds stress force. Approaching the L-H transition, the LCO is excited and the GAM decays. In the LCO phase, the GAM driving force is possibly suppressed by the nonlocal turbulence amplitude modulation by the LCO.