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arXiv · 1404.4086

Peeling-off of the external kink modes at tokamak plasma edge

L. J. Zheng·M. Furukawa
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Abstract

It is pointed that there is a current jump between the edge plasma inside the last closed magnetic surface and the scrape-off layer and the current jump can lead the external kink modes to convert to the tearing modes, due to the current interchange effects [L. J. Zheng and M. Furukawa, Phys. Plasmas 17, 052508 (2010)]. The magnetic reconnection in the presence of tearing modes subsequently causes the tokamak edge plasma to be peeled off to link to the diverters. In particular, the peeling or peeling-ballooning modes can become the "peeling-off" modes in this sense. This phenomenon indicates that the tokamak edge confinement can be worse than the expectation based on the conventional kink mode picture.

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L. J. Zheng, M. Furukawa. 2014-04-15. Peeling-off of the external kink modes at tokamak plasma edge. https://doi.org/10.1063/1.4894105

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