RE beam generation in MGI disruptions on COMPASS.

0482534 - ÚFP 2018 RIV FR eng C - Conference Paper (international conference)
Ficker, Ondřej - Mlynář, Jan - Tomešová, Eva - Vlainić, M. - Weinzettl, Vladimír - Urban, Jakub - Čeřovský, Jaroslav - Farník, Michal - Markovič, Tomáš - Papřok, Richard - Vondráček, Petr - Imríšek, Martin - Tomeš, Matěj - Havlíček, Josef - Varju, Jozef - Varavin, Mykyta - Bogár, Ondrej - Havránek, Aleš - Gospodarczyk, M. - Rabinski, M. - Jakubowski, M. - Malinovski, K. - Zebrowski, J. - Plyusnin, V. - Papp, G. - Pánek, Radomír - Hron, Martin
RE beam generation in MGI disruptions on 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 P5.126. 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 MŠMT LG14002; GA MŠMT(CZ) LM2015045; GA MŠMT(CZ) 8D15001
EU Projects: European Commission(XE) 633053 - EUROfusion
Institutional support: RVO:61389021
Keywords : RE * massive gas injection (MGI) * disruptions * HXR * ECE * fast cameras
OECD category: Fluids and plasma physics (including surface physics)

In the experiments with the massive gas injection (MGI) triggered disruptions in the COMPASS tokamak, post-disruptive runaway electron (RE) beams are generated occasionally. In this contribution, a relatively large set of discharges from the recent years is analysed in order to improve our understanding of the processes behind the beam generation. It seems that despite the low toroidal field applied in the discharges (typically 1.15 T) the magnetic perturbations may be small enough to allow the acceleration and confinement of the electrons. The influence of the different components and different sections of the frequency spectrum of the magnetic perturbations on the beam generation and RE beam current is examined. Fast visible camera images are also analysed. The relevance of COMPASS runaway electron experiments for large machines is discussed. Moreover, the potential of less common diagnostic tools (Cherenkov detector, vertical ECE, ...) to clarify the role of the pre-disruption fast electron population and the influence of prompt runaway electron losses in the current quench is discussed using the recent test measurements.
Permanent Link: http://hdl.handle.net/11104/0277962