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Return To: Session THP1 - Theory 1 (Friday, 23 October)
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(THP1/13) The ``Positive'' Magnetic Islands Conception and its Applications to T-11M Experiments

   
S. V. Mirnov , I. Semenov , A. M. Belov , E. A. Azizov 
 
State Research Center TRINITI, Troitsk, 142092 Moscow Region, Russian Federation

Abstract
A situation in tokamaks is analyzed in which the development of strong plasma current filamentation  leads to nonlinear magnetic islands formation near resonant magnetic surfaces. It is shown that, along with the usual ``negative'' magnetic islands, in which the modulation of the perturbation currents is negative, ``positive'' islands can form in local regions with the positive current modulation. The ``positive'' magnetic islands can be a reason of the ``hot spot'' in plasma center during sawtooth crash. Also the ``positive'' islands, probably, plays the important role in m=2 development during the major disruption and in the locked modes  dynamics.

 

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IAEA 1999