Experimental runaway electron current estimation in COMPASS tokamak

0501873 - ÚFP 2019 RIV CH eng J - Journal Article
Vlainic, M. - Ficker, Ondřej - Mlynář, Jan - Tomešová, Eva
Experimental runaway electron current estimation in COMPASS tokamak.
Atoms. Roč. 7, č. 1 (2019), č. článku 7010012. ISSN 2218-2004
R&D Projects: GA MŠMT(CZ) LM2011021; GA MŠMT(CZ) 8D15001
EU Projects: European Commission(XE) 633053 - EUROfusion
Institutional support: RVO:61389021
Keywords : runaway electron * plasma current * fusion plasma * tokamak
OECD category: Fluids and plasma physics (including surface physics)
https://www.mdpi.com/2218-2004/7/1/12/htm

Runaway electrons present a potential threat to the safe operation of future nuclear fusion large facilities based on the tokamak principle (e.g., ITER). The article presents an implementation of runaway electron current estimations at COMPASS tokamak. The method uses a theoretical method developed by Fujita et al., with the difference in using experimental measurements from EFIT and Thomson scattering. The procedure was explained on the COMPASS discharge number 7298, which has a significant runaway electron population. Here, it was found that at least 4 kA of the plasma current is driven by the runaway electrons. Next, the method aws used on the set of plasma discharges with the variable electron plasma density. The difference in the plasma current was explained by runaway electrons, and their current was estimated using the aforementioned method. The experimental results are compared with the theory and simulation. The comparison presented some disagreements, showing the possible direction for the code development. Additional application on runaway electron energy limit is also addressed.
Permanent Link: http://hdl.handle.net/11104/0293853