TY - JOUR
T1 - Toroidal momentum channeling of geodesic acoustic modes driven by fast ions
AU - Sasaki, M.
AU - Kasuya, N.
AU - Itoh, K.
AU - Kosuga, Y.
AU - Lesur, M.
AU - Hallatschek, K.
AU - Itoh, S. I.
N1 - Funding Information:
This work was partly supported by a grant-in-aid for scientific research of JSPS, Japan (JP16K18335, JP16H02442, JP15H02335, JP15H02155, JP24740372, JP21224014) and by the collaboration programs of NIFS (NIFS14KNST072, NIFS15KNST089) and of the RIAM of Kyushu University, and Asada Science foundation.
Publisher Copyright:
© 2017 IAEA, Vienna.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2017/3
Y1 - 2017/3
N2 - 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.
AB - 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.
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U2 - 10.1088/1741-4326/aa4eb4
DO - 10.1088/1741-4326/aa4eb4
M3 - Article
AN - SCOPUS:85013387809
SN - 0029-5515
VL - 57
JO - Nuclear Fusion
JF - Nuclear Fusion
IS - 3
M1 - 036025
ER -