Efficient and customizable simulations of the nonlinear plasma response to magnetic field*

We explore nonlinear properties of the plasma response to externally-applied magnetic field perturbations, in the vicinity of a resonant surface, using the newly developed Trixi.jl package. Written in the Julia language, the Trixi.jl provides a flexible, high-performance framework for solving hyperbolic differential equations on customizable, geometric meshes. Numerical simulations are compared with newly derived analytic solutions for the magnetic field near the resonant surfaces, enabling quantitative examination of how the local, nonlinear behavior can affect the global plasma response.

Symmetry breaking magnetic field perturbations can have a significant impact on fusion plasma performance in tokamaks and stellarators alike. Understanding the characteristics of the nonlinear plasma response is critical to controlling and optimizing plasma performance in a range of settings.