TY - JOUR
T1 - Nonlinear excitation of energetic particle driven geodesic acoustic mode by resonance overlap with Alfvén instability in ASDEX Upgrade
AU - The ASDEX Upgrade Team
AU - Wang, Hao
AU - Lauber, Philipp
AU - Todo, Yasushi
AU - Suzuki, Yasuhiro
AU - Li, Hanzheng
AU - Idouakass, Malik
AU - Wang, Jialei
AU - Adulsiriswad, Panith
AU - Zoletnik, S.
AU - Zohm, H.
AU - Zito, A.
AU - Zimmermann, C. F.B.
AU - Zilker, M.
AU - Zibrov, A.
AU - Zholobenko, W.
AU - Zhang, W.
AU - Zehetbauer, T.
AU - Zammuto, I.
AU - Zagórski, R.
AU - Yu, Q.
AU - Yoo, C.
AU - Yang, Q.
AU - Wolfrum, E.
AU - Wolf, R.
AU - Wischmeier, M.
AU - Wiringer, B.
AU - Willensdorfer, M.
AU - White, A. E.
AU - Wendler, D.
AU - Weiland, M.
AU - Wang, X.
AU - Wagner, D.
AU - von Toussaint, U.
AU - Voitsekhovitch, I.
AU - Viezzer, E.
AU - Vierle, T.
AU - Vicente, J.
AU - Vianello, N.
AU - Verdoolaege, G.
AU - Verdier, T.
AU - Varoutis, S.
AU - Varela, P.
AU - Vanovac, B.
AU - Vannini, F.
AU - van Zeeland, M.
AU - Tripský, M.
AU - Maquet, V.
AU - Lyssoivan, A.
AU - Lerche, E.
AU - Jachmich, S.
N1 - Publisher Copyright:
© The Author(s) 2024.
PY - 2025/12
Y1 - 2025/12
N2 - The Alfvén instability nonlinearly excited the energetic-particle-driven geodesic acoustic mode on the ASDEX-Upgrade tokamak, as demonstrated experimentally. The mechanism of the energetic-particle-driven geodesic acoustic mode excitation and the mode nonlinear evolution is not yet fully understood. In the present work, a first-principles simulation using the MEGA code investigated the mode properties in both the linear growth and nonlinear saturated phases. Here we show that the simulation successfully reproduced the excitation and coexistence of these two modes, and agreed with the experimental results well. Conclusive evidence showed that the resonance overlap is the excitation mechanism of the energetic-particle-driven geodesic acoustic mode. In the linear growth phase, energetic particles that satisfied different resonance conditions excited the Alfvén instability, which then caused energetic particle redistribution in phase space. These redistributed energetic particles caused resonance overlap, exciting the energetic-particle-driven geodesic acoustic mode in the nonlinear phase.
AB - The Alfvén instability nonlinearly excited the energetic-particle-driven geodesic acoustic mode on the ASDEX-Upgrade tokamak, as demonstrated experimentally. The mechanism of the energetic-particle-driven geodesic acoustic mode excitation and the mode nonlinear evolution is not yet fully understood. In the present work, a first-principles simulation using the MEGA code investigated the mode properties in both the linear growth and nonlinear saturated phases. Here we show that the simulation successfully reproduced the excitation and coexistence of these two modes, and agreed with the experimental results well. Conclusive evidence showed that the resonance overlap is the excitation mechanism of the energetic-particle-driven geodesic acoustic mode. In the linear growth phase, energetic particles that satisfied different resonance conditions excited the Alfvén instability, which then caused energetic particle redistribution in phase space. These redistributed energetic particles caused resonance overlap, exciting the energetic-particle-driven geodesic acoustic mode in the nonlinear phase.
UR - http://www.scopus.com/inward/record.url?scp=85214352379&partnerID=8YFLogxK
U2 - 10.1038/s41598-024-82577-3
DO - 10.1038/s41598-024-82577-3
M3 - Article
AN - SCOPUS:85214352379
SN - 2045-2322
VL - 15
JO - Springer Scientific Reports
JF - Springer Scientific Reports
IS - 1
M1 - 1130
ER -