EFD-C(10)06/03
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JET Disruption Studies in
Support of ITER
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V. Riccardo, G. Arnoux, P. Cahyna, T.C. Hender, A. Huber, S. Jachmich,
V. Kiptily, R. Koslowski, L. Krlin, M. Lehnen, A. Loarte, E. Nardon,
R. Paprok, D. Tskhakaya and JET EFDA contributors
Abstract.
Plasma disruptions affect plasma facing and structural components of tokamaks due
to electromechanical forces, thermal loads and generation of high energy runaway
electrons. Asymmetries in poloidal halo and toroidal plasma current can now be routinely measured
in four positions 90o apart. Their assessment is used to validate the design of the ITER
vessel support system and its in-vessel components. The challenge of disruption thermal loads
comes from both the short duration over which a large energy has to be lost and the potential
for asymmetries. The focus of this paper will be on localised heat loads. Resonant
magnetic perturbations failed to reduce the generation of runaway electrons in JET. An explanation of
the limitations applying to these attempts is offered together with a minimum guideline. The
REs generated by a moderate, but fast, Ar injection in limiter plasmas show evidence of milder
and more efficient losses due to the high Ar background density.
Preprint of Paper to be submitted for publication in Proceedings of the
37th EPS Conference on Plasma Physics, Dublin, Ireland.
(21st June 2010 - 25th June 2010)
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