Electric field induced by radial redistribution of the energetic ion pressure in a fusion plasma

TL;DR

This paper demonstrates through gyrokinetic theory that radial redistribution of energetic ion pressure can generate significant radial electric fields in tokamaks, with implications for plasma confinement.

Contribution

It reveals that trapped energetic ions are more effective than isotropic ions in generating radial electric fields, highlighting the role of alpha particles in fusion plasma confinement.

Findings

Radial electric fields can be generated by energetic ion pressure redistribution.

Trapped energetic ions are more effective than isotropic ions in this process.

Alpha particles may enhance core plasma confinement in fusion reactors.

Abstract

It is found by using the gyrokinetic theory that significant radial electric fields, or zonal flows, can be generated by the radial redistribution of energetic ion pressure in a tokamak fusion device. Trapped energetic ions are more effective to generate the radial electric field than the isotropic energetic ions. This suggests that the energetic $\alpha$ particles produced by DT fusion may induce significant radial electric field and thus help to improve the core plasma confinement in a fusion reactor.