Time-resonant tokamak plasma edge instabilities?
Author | |
Abstract |
For a two week period during the Joint European Torus 2012 experimental campaign, the same high confinement plasma was repeated 151 times. The dataset was analysed to produce a probability density function (pdf) for the waiting times between edge-localized plasma instabilities (ELMs). The result was entirely unexpected. Instead of a smooth single peaked pdf, a succession of 4-5 sharp maxima and minima uniformly separated by 7-8 ms intervals was found. Here we explore the causes of this newly observed phenomenon, and conclude that it is either due to a naturally occurring self-organized plasma phenomenon or an interaction between the plasma and a real-time control system. If the maxima are a result of 'resonant' frequencies at which ELMs can be triggered more easily, then future ELM control techniques can, and probably will, use them. Either way, these results demand a deeper understanding of the ELM process. |
Year of Publication |
2014
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Journal |
Plasma Physics and Controlled Fusion
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Volume |
56
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Number |
7
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Issue |
7
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Number of Pages |
075017
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Date Published |
Jul
|
ISBN Number |
0741-3335
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URL |
http://www.euro-fusionscipub.org/wp-content/uploads/2014/11/EFDP13058.pdf
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DOI |
10.1088/0741-3335/56/7/075017
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PId |
63d8b3401376cbc0bda7a01df91ddc7b
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Alternate Journal |
Plasma Phys. Control. Fusion
|
Label |
OA
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Journal Article
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