@article{8f7426aa6757449e8a674dabb1bfb2d3,
title = "Enhanced performance in fusion plasmas through turbulence suppression by megaelectronvolt ions",
abstract = "Alpha particles with energies on the order of megaelectronvolts will be the main source of plasma heating in future magnetic confinement fusion reactors. Instead of heating fuel ions, most of the energy of alpha particles is transferred to electrons in the plasma. Furthermore, alpha particles can also excite Alfv{\'e}nic instabilities, which were previously considered to be detrimental to the performance of the fusion device. Here we report improved thermal ion confinement in the presence of megaelectronvolts ions and strong fast ion-driven Alfv{\'e}nic instabilities in recent experiments on the Joint European Torus. Detailed transport analysis of these experiments reveals turbulence suppression through a complex multi-scale mechanism that generates large-scale zonal flows. This holds promise for more economical operation of fusion reactors with dominant alpha particle heating and ultimately cheaper fusion electricity.",
author = "{JET Contributors} and S. Mazzi and J. Garcia and D. Zarzoso and Kazakov, {Ye O.} and J. Ongena and M. Dreval and M. Nocente and {\v S}tancar and G. Szepesi and J. Eriksson and A. Sahlberg and S. Benkadda and N. Abid and K. Abraham and P. Abreu and O. Adabonyan and P. Adrich and M. Afzal and T. Ahlgren and L. Aho-Mantila and N. Aiba and M. Airila and M. Akhtar and R. Albanese and M. Alderson-Martin and D. Alegre and S. Aleiferis and A. Aleksa and E. Alessi and P. Aleynikov and J. Algualcil and M. Beurskens and M. Bowden and J. Citrin and {De Bock}, M. and E. Delabie and Donn{\'e}, {A. J.H.} and A. Dvornova and F. Felici and A. Ho and Huijsmans, {G. T.A.} and P. Huynh and F. Jaulmes and A. Kappatou and M. Kempenaars and M. Marin and {van de Plassche}, {K. L.} and P. Rodrigues and Sips, {A. C.C.} and G. Snoep and Meekes, {Cederik J.}",
note = "Funding Information: We thank M. Baruzzo and F. Nave for the preparation and execution of JET experiments discussed in this paper; E. de la Luna for support in detailing the experimental diagnostics of JET; A. Ho for assistance in processing the experimental data; T. G{\"o}rler for providing essential advice to ensure the correct numerical setup for the GENE modelling reported in this paper; Y. Camenen, X. Garbet and A. Bierwage for fruitful discussions about the gyrokinetic analyses; G. Giruzzi for valuable suggestions on the article strategy. The simulations were performed on the IRENE Joliot-Curie HPC system, in the framework of the PRACE projects IONFAST and AFIETC, led by J. Garcia, and on the CINECA Marconi HPC within the project GENE4EP, led by D. Zarzoso. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement no. 633053. The views and opinions express herein do not necessarily reflect those of the European Commission. Part of the work by Ye. O. Kazakov and J.Ongena was also carried out in the framework of projects done for the ITER Scientist Fellow Network (ISFN). Funding Information: We thank M. Baruzzo and F. Nave for the preparation and execution of JET experiments discussed in this paper; E. de la Luna for support in detailing the experimental diagnostics of JET; A. Ho for assistance in processing the experimental data; T. G{\"o}rler for providing essential advice to ensure the correct numerical setup for the GENE modelling reported in this paper; Y. Camenen, X. Garbet and A. Bierwage for fruitful discussions about the gyrokinetic analyses; G. Giruzzi for valuable suggestions on the article strategy. The simulations were performed on the IRENE Joliot-Curie HPC system, in the framework of the PRACE projects IONFAST and AFIETC, led by J. Garcia, and on the CINECA Marconi HPC within the project GENE4EP, led by D. Zarzoso. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement no. 633053. The views and opinions express herein do not necessarily reflect those of the European Commission. Part of the work by Ye. O. Kazakov and J.Ongena was also carried out in the framework of projects done for the ITER Scientist Fellow Network (ISFN). Publisher Copyright: {\textcopyright} 2022, The Author(s), under exclusive licence to Springer Nature Limited.",
year = "2022",
month = jul,
day = "1",
doi = "10.1038/s41567-022-01626-8",
language = "English",
volume = "18",
pages = "776--782",
journal = "Nature Physics",
issn = "1745-2473",
publisher = "Nature Publishing Group",
number = "7",
}