Observations of Alfvénic-character oscillations in ohmic plasmas on the COMPASS tokamak.

0482689 - ÚFP 2018 RIV FR eng C - Conference Paper (international conference)
Markovič, Tomáš - Melnikov, A. - Seidl, Jakub - Eliseev, L. - Havlíček, Josef - Havránek, Aleš - Hron, Martin - Imríšek, Martin - Kovařík, Karel - Medvedev, S. - Bogár, Klára - Mlynář, Jan - Naydenkova, Diana - Pánek, Radomír - Stöckel, Jan - Varju, Jozef - Weinzettl, Vladimír
Observations of Alfvénic-character oscillations in ohmic plasmas on the COMPASS tokamak.
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 P5.005. 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
Institutional support: RVO:61389021
Keywords : Alfvén Eigenmode * Magnetic Confinement Fusion * MHD
OECD category: Fluids and plasma physics (including surface physics)

In plasma magnetic confinement devices, a significant presence of superthermal Energetic Particles (EP) (e.g. from auxiliary plasma heating systems) can drive instabilities via resonance of particle velocity with plasma Alfvén velocity, which can in turn negatively affect the EP confinement. However, there have been reports of plasma Alfvén eigenmode oscillations
in purely ohmically-heated plasmas on several experimental devices. In this paper we report observation of similar Alfvén eigenmode oscillations in ohmically heated plasmas on the COMPASS tokamak and classify them with respect to the reports from other devices from the perspective of mode frequency scaling, localization and possible excitation mechanisms.

Permanent Link: http://hdl.handle.net/11104/0278103