Characterization of the I-phase regime at TCV
Autor: | M. Griener, C. Wüthrich, Y. Wang, D. Brida, M. Faitsch, N. Offeddu, C. Theiler, the TCV Team, the EUROfusion Tokamak Exploitation Team |
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Jazyk: | angličtina |
Rok vydání: | 2024 |
Předmět: | |
Zdroj: | Nuclear Fusion, Vol 65, Iss 1, p 016041 (2024) |
Druh dokumentu: | article |
ISSN: | 1741-4326 0029-5515 |
DOI: | 10.1088/1741-4326/ad96cb |
Popis: | The I-phase is an H-mode confinement regime of tokamaks characterized by limit cycle oscillations, the so-called LCOs or bursts. These bursts are the manifestation of a periodic flattening of the plasma edge pressure profile. The profile flattening is caused by increased radial transport, driven by a high-frequency plasma edge mode that periodically appears. This short-living mode is intrinsically connected to each burst. It vanishes once the profiles are fully flattened, and it reestablishes during profile recovery once critical gradients are reached and a new cycle begins. In this paper, we describe for the first time the unambiguous presence of the I-phase at the tokamak à configuration variable (TCV). As the I-phase confinement regime is found in the parameter regime between the L-mode and the fully developed H-mode, it is often confused with dithers between H-mode and L-mode. Therefore, we are highlighting the differences between these two phenomena. Furthermore, we show the two-dimensional dynamics of the I-phase mode and bursts and the associated filamentary transport, enabled by the outstanding capabilities of the 2D TCV Gas Puff Imaging diagnostics. |
Databáze: | Directory of Open Access Journals |
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