TY - JOUR
T1 - Quantification of Turbulent Driving Forces for the Geodesic Acoustic Mode in the JFT-2M Tokamak
AU - Kobayashi, T.
AU - Sasaki, Makoto
AU - Ido, T.
AU - Kamiya, K.
AU - Miura, Y.
AU - Nagashima, Y.
AU - Ida, K.
AU - Inagaki, S.
AU - Fujisawa, A.
AU - Itoh, Sanae
AU - Itoh, K.
N1 - Funding Information:
We thank G. D. Conway, K. Hallatschek, and G. Birkenmeier for useful discussions, and the late H. Maeda, Y. Hamada, M. Mori, Y. Kamada, S. Sakakibara, and K. Hoshino for strong support. This work is partly supported by the Grant-in-Aid for Scientific Research of Japan Society for the Promotion of Science, Japan (Grants No. 17K14898, No. 16K18335, No. 16H02442, No. 15H02155). The collaboration programs of National Institute for Quantum and Radiological Science and Technology and of Research Institute for Applied Mechanics, Kyushu University are also appreciated.
Publisher Copyright:
© 2018 American Physical Society.
PY - 2018/1/26
Y1 - 2018/1/26
N2 - We investigate spatial structures of turbulence and turbulent transport modulated by the geodesic acoustic mode (GAM), from which the excitation mechanism of the GAM is discussed. The GAM is found to be predominantly excited through a localized Reynolds stress force, rather than the dynamic shearing force. The evaluated growth rate is larger than the linear damping coefficients and is on the same order of magnitude as the effective growth rate evaluated from time evolution in the GAM kinetic energy.
AB - We investigate spatial structures of turbulence and turbulent transport modulated by the geodesic acoustic mode (GAM), from which the excitation mechanism of the GAM is discussed. The GAM is found to be predominantly excited through a localized Reynolds stress force, rather than the dynamic shearing force. The evaluated growth rate is larger than the linear damping coefficients and is on the same order of magnitude as the effective growth rate evaluated from time evolution in the GAM kinetic energy.
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U2 - 10.1103/PhysRevLett.120.045002
DO - 10.1103/PhysRevLett.120.045002
M3 - Article
C2 - 29437414
AN - SCOPUS:85041126465
VL - 120
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 4
M1 - 045002
ER -