Self-sustained annihilation of magnetic islands in helical plasmas

Kimitaka Itoh, Sanae Itoh, Masatoshi Yagi

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The evolution of the magnetic island which is induced by the resonant deformation by external currents in helical systems (such as the large helical device (LHD) [A. Iiyoshi, Phys. Plasmas 2, 2349 (1995)]) is analyzed. The defect of the bootstrap current, caused by the magnetic island, has a parity which reduces the size of the magnetic island, if the bootstrap current enhances the vacuum rotational transform. The width of magnetic island can be suppressed to the level of ion banana width if the pressure gradient exceeds a threshold value. This island annihilation is self-sustained. That is, the annihilation continues, for fixed beta value, until the external drive for island generation exceeds a threshold. The effects of the reversal of the direction of the bootstrap current and of the sign of radial electric field are also investigated. The possibility of the neoclassical tearing mode in the LHD-like plasma is discussed.

Original languageEnglish
Pages (from-to)1-6
Number of pages6
JournalPhysics of Plasmas
Volume12
Issue number7
DOIs
Publication statusPublished - Jul 1 2005

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magnetic islands
thresholds
pressure gradients
parity
vacuum
electric fields
defects
ions

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics

Cite this

Self-sustained annihilation of magnetic islands in helical plasmas. / Itoh, Kimitaka; Itoh, Sanae; Yagi, Masatoshi.

In: Physics of Plasmas, Vol. 12, No. 7, 01.07.2005, p. 1-6.

Research output: Contribution to journalArticle

Itoh, Kimitaka ; Itoh, Sanae ; Yagi, Masatoshi. / Self-sustained annihilation of magnetic islands in helical plasmas. In: Physics of Plasmas. 2005 ; Vol. 12, No. 7. pp. 1-6.
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