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 Alfvénic 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 Alfvénic 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.
Original languageEnglish
Pages (from-to)776-782
Number of pages14
JournalNature Physics
Volume18
DOIs
Publication statusPublished - 30 Jun 2022

Keywords

  • magnetically confined plasmas
  • nonlinear phenomena
  • nuclear fusion and fission

Fingerprint

Dive into the research topics of 'Enhanced performance in fusion plasmas through turbulence suppression by megaelectronvolt ions'. Together they form a unique fingerprint.

Cite this