Characterization of the electron density profile dynamic and flow velocity modulation during oscillations close to the L-H threshold at COMPASS.

0482817 - ÚFP 2018 RIV FR eng C - Conference Paper (international conference)
Refy, D.I. - Zoletnik, S. - Grover, Ondřej - Seidl, Jakub - Hron, Martin - Dunai, D. - Anda, G. - Bencze, A. - Háček, Pavel - Krbec, Jaroslav - Weinzettl, Vladimír
Characterization of the electron density profile dynamic and flow velocity modulation during oscillations close to the L-H threshold at COMPASS.
EPS 2017: 44th European Physical Society Conference on Plasma Physics. Vol. 41F. Mulhouse: European Physical Society, 2017 - (Fajardo, M.; Westerhof, E.; Riconda, C.; Melzer, A.; Bret, A.; Dromey, B.), č. článku P4.178. Europhysics Conference Abstracts (ECA). ISBN 979-10-96389-07.
[EPS 2017 Conference on Plasma Physics/44./. Belfast (IE), 26.06.2017-30.06.2017]
R&D Projects: GA ČR(CZ) GA16-25074S; GA MŠMT(CZ) 8D15001; GA MŠMT(CZ) LM2015045
EU Projects: European Commission(XE) 633053 - EUROfusion
Institutional support: RVO:61389021
Keywords : tokamak * COMPASS
OECD category: Fluids and plasma physics (including surface physics)

A new confinement regime is being investigated as a candidate for a limit cycle oscillation (cLCO) at the COMPASS [1] tokamak, appearing near the L-H transition, and identified by a low frequency (~3-5 kHz), divertor D alpha oscillation. Similar phenomena were observed at the JET [2], ASDEX Upgrade (AUG)[3] and other tokamaks as well. This contribution aims at adding the COMPASS results to a previous study [4] which addressed the JET and AUG phenomena in terms of density pedestal dynamics and magnetic oscillation studies. The outstanding per formance of the COMPASS Lithium beam emission spectroscopy (Li-BES) system enables us to resolve the phenomenon in more detail, namely the flow velocity and turbulence amplitude modulation.
Permanent Link: http://hdl.handle.net/11104/0278321