Since the theoretical description of the three-ion scheme back in 2015 , the scheme has been tested and proven in several fusion devices such as Alcator C-Mod, JET and AUG. The main idea underlying this radiofrequency (RF) scheme comes from the polarization of the wave. In essence, what is sought, is the maximization of the electric field component that rotates as the ions do around the magnetic field. This condition is typically reached when the resonance location of the minority ion species coincides with the so-called L-cutoff of the wave. The result? A highly dominant ion absorption of the wave and a very energetic ion distribution.
We are very happy to announce that the recently published paper “Physics and applications of three-ion ICRF scenarios for fusion research” has been selected as a featured paper in the prestigious Physics of Plasmas journal, where two members of our group, Mervi Mantsinen and Dani Gallart, have collaborated. The paper presents many of the advances on this scheme during these last years, especially from the experimental point of view and the developed theoretical framework.
The article will take you on a tour through the main concepts hinging around the three ion scheme. It will show you how to prepare the recipe for the scheme to work, what are the expected outcomes depending upon the atomic mass of the selected resonant species and multiple applications of the scheme which go way beyond the RF heating scope. Furthermore, it shows interesting results of some experiments at JET conducted in preparation for ITER studies such as the successful use of the scheme to generate fusion-born alpha particles and the effect of fast ions on plasma confinement under ITER-relevant heating conditions. All this with many proof-of-principle demonstrations through experimental observations which confirm the validity of the scheme. We encourage you to have a read and go a little deeper in this novel scheme which opens the door to many new possibilities in fusion research.
The members of the Fusion group would like to acknowledge the excellent work carried out by the whole team and, especially, by Dr Yevgen Kazakov from Laboratory for Plasma Physics of the Ecole Royale Militaire – Koninklijke Militaire School (LPP-ERM/KMS) who has been leading this research.