Toroidal momentum channeling of geodesic acoustic modes driven by fast ions

Makoto Sasaki, Naohiro Kasuya, K. Itoh, Yusuke Kosuga, M. Lesur, K. Hallatschek, Sanae Itoh

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Toroidal momentum channeling by fast ion-driven geodesic acoustic mode (EGAM) is proposed based on a quasi-linear analysis. We focus on a branch due to the magnetic drift resonance. Without the magnetic drift resonance, the eigenfunction of the EGAM has up-down anti-symmetric property in the poloidal direction, and the toroidal momentum flux by the EGAM is zero. If the magnetic drift resonance is considered, the up-down anti-symmetry in the poloidal eigenfunction is violated, and, as a result, the toroidal momentum flux becomes finite. Comparing its magnitude to the other processes such as external momentum input, and the turbulent residual stress, the momentum flux induced by the EGAM is found to be significant in the total momentum balance. This suggests that EGAMs can be used as a control knob for the toroidal rotation.

Original languageEnglish
Article number036025
JournalNuclear Fusion
Volume57
Issue number3
DOIs
Publication statusPublished - Mar 1 2017

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momentum
acoustics
ions
eigenvectors
knobs
antisymmetry
residual stress

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Condensed Matter Physics

Cite this

Toroidal momentum channeling of geodesic acoustic modes driven by fast ions. / Sasaki, Makoto; Kasuya, Naohiro; Itoh, K.; Kosuga, Yusuke; Lesur, M.; Hallatschek, K.; Itoh, Sanae.

In: Nuclear Fusion, Vol. 57, No. 3, 036025, 01.03.2017.

Research output: Contribution to journalArticle

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