E x B Drift Particle Transport in Tokamaks

In tokamaks, modification of the plasma profiles can reduce plasma transport, improving particle confinement. However, this improvement is still not completely understood. In this work, we consider a drift wave test particle model to investigate the influence of the electric and magnetic field profiles on plasma transport. Test particle orbits subjected to E x B drift are numerically integrated and their transport coefficient is obtained. We conclude that sheared profiles reduce particle transport, even for high amplitude perturbations. In particular, nonmonotonic electric and magnetic fields produce shearless transport barriers, which are particularly resistant to perturbations and reduce even more the transport coefficient.

Automated summary

In this study, the influence of electric and magnetic field profiles on plasma transport in tokamaks is investigated. It is found that sheared electric and magnetic fields can reduce particle transport, and nonmonotonic fields can produce shearless transport barriers, which are highly resistant to perturbations and further decrease the transport coefficient.