Analysis of the alpha particle transport induced by Alfven eigenmodes and fish-bones in JET DT discharges: multiple energetic particle simulations
Abstract
The present study is dedicated to analyze the extensive fast ion (FI) induced perturbations in ion cyclotron resonance heating (ICRH) dominated plasmas in JET deuterium–tritium (D–T) discharges, the closest experiment to reactor-like operation. A set of nonlinear simulations are performed with the gyro-fluid FAR3d code to reproduce the FI induced activity and energetic particle (EP) transport observed in the discharge 99896 by multiple EP populations. Well validated simulations with JET D–T diagnostics show that Toroidal Alfvén eigenmodes (TAEs) and fish-bone are destabilized by ICRH accelerated passing D and trapped H ions, respectively. Multiple EP simulations show important nonlinear couplings between EP species, leading to a strong effect on the alpha particle confinement even in the alpha particles do not destabilize EP modes. Simulations including trapped H and alpha particles indicate fish-bones may induce alpha particle losses up to 3 % . The situation is different with respect to TAEs, which have a smaller impact on the alpha particle transport, leading to negligible losses. In addition, the generation of shear flows during the saturation phase of TAE and fish-bones is observed in the simulations. Shear flows induced by TAEs in the inner-middle plasma region are almost two times larger compared to the shear flows caused by the fish-bone in the inner plasma region. Shear flow generation by AE/fish-bones may have an important impact in the thermal plasma and alpha particle confinement of devices as ITER and JT60SA. Consequently, nonlinear effects in multiple EP populations must be considered in the analysis of EP transport. It is shown that this is a fundamental result that has to be considered to be properly evaluate fusion power in reactor relevant plasmas.
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BibTeX
@article{varela2026analysis,
title = {{Analysis of the alpha particle transport induced by Alfven eigenmodes and fish-bones in JET DT discharges: multiple energetic particle simulations}},
author = {J. Varela and J. Garcia and D. Zarzoso and S. Mazzi and Y. Kazakov and Z. Stancar and M. Baruzzo and J. Ongena and D.A. Spong and L. Garcia and Y. Ghai and J. Ortiz and M. Poradzinski and S. Sharapov and M. Fitzgerald and B. Breizman and D. del Castillo-Negrete and F. Waelbroeck and S. Menmuir and H.J. Sun and D. Kos and A. Boboc and N.C. Hawkes},
journal = {Nuclear Fusion},
year = {2026},
month = jul,
doi = {10.1088/1741-4326/ae827d},
url = {https://hal.science/hal-05845182v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Analysis of the alpha particle transport induced by Alfven eigenmodes and fish-bones in JET DT discharges: multiple energetic particle simulations
AU - J. Varela
AU - J. Garcia
AU - D. Zarzoso
AU - S. Mazzi
AU - Y. Kazakov
AU - Z. Stancar
AU - M. Baruzzo
AU - J. Ongena
AU - D.A. Spong
AU - L. Garcia
AU - Y. Ghai
AU - J. Ortiz
AU - M. Poradzinski
AU - S. Sharapov
AU - M. Fitzgerald
AU - B. Breizman
AU - D. del Castillo-Negrete
AU - F. Waelbroeck
AU - S. Menmuir
AU - H.J. Sun
AU - D. Kos
AU - A. Boboc
AU - N.C. Hawkes
PY - 2026
DA - 2026/07/13
JO - Nuclear Fusion
DO - 10.1088/1741-4326/ae827d
UR - https://hal.science/hal-05845182v1
AB - The present study is dedicated to analyze the extensive fast ion (FI) induced perturbations in ion cyclotron resonance heating (ICRH) dominated plasmas in JET deuterium–tritium (D–T) discharges, the closest experiment to reactor-like operation. A set of nonlinear simulations are performed with the gyro-fluid FAR3d code to reproduce the FI induced activity and energetic particle (EP) transport observed in the discharge 99896 by multiple EP populations. Well validated simulations with JET D–T diagnostics show that Toroidal Alfvén eigenmodes (TAEs) and fish-bone are destabilized by ICRH accelerated passing D and trapped H ions, respectively. Multiple EP simulations show important nonlinear couplings between EP species, leading to a strong effect on the alpha particle confinement even in the alpha particles do not destabilize EP modes. Simulations including trapped H and alpha particles indicate fish-bones may induce alpha particle losses up to 3 % . The situation is different with respect to TAEs, which have a smaller impact on the alpha particle transport, leading to negligible losses. In addition, the generation of shear flows during the saturation phase of TAE and fish-bones is observed in the simulations. Shear flows induced by TAEs in the inner-middle plasma region are almost two times larger compared to the shear flows caused by the fish-bone in the inner plasma region. Shear flow generation by AE/fish-bones may have an important impact in the thermal plasma and alpha particle confinement of devices as ITER and JT60SA. Consequently, nonlinear effects in multiple EP populations must be considered in the analysis of EP transport. It is shown that this is a fundamental result that has to be considered to be properly evaluate fusion power in reactor relevant plasmas.
SN - 0029-5515
SN - 1741-4326
ER -