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Suppression of runaway electron generation by massive helium injection after induced disruptions on TEXTOR

Part of: Energetic Electrons Focus on Fusion

Published online by Cambridge University Press:  02 September 2015

A. Lvovskiy ,
H. R. Koslowski ,
L. Zeng  and
The TEXTOR Team
A. Lvovskiy*
Affiliation:
Institut für Energie- und Klimaforschung, Plasmaphysik, Forschungszentrum Jülich GmbH, Jülich 52425, Germany
H. R. Koslowski
Affiliation:
Institut für Energie- und Klimaforschung, Plasmaphysik, Forschungszentrum Jülich GmbH, Jülich 52425, Germany
L. Zeng
Affiliation:
Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, PR China
*
†Email address for correspondence: [email protected]
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Abstract

Disruptions with runaway electron generation have been deliberately induced by injection of argon using a disruption mitigation valve. A second disruption mitigation valve has been utilised to inject varying amounts of helium after a short time delay. No generation of runaway electrons has been observed when more than a critical amount of helium has been injected no later than 5 ms after the triggering of the first valve. The required amount of helium for suppression of runaway electron generation is up to one order of magnitude lower than the critical density according to Connor & Hastie (1975) and Rosenbluth & Putvinski (1997).

Type
Research Article
Information
Journal of Plasma Physics , Volume 81 , Issue 5 , October 2015 , 475810507
Copyright
© Cambridge University Press 2015 

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