### 07-26, 10:55–11:25 (US/Eastern), Online talks and posters

In this work, we present progress towards the development of a new code written in the Julia programming language for evaluating global (linear) ideal MHD stability in stellarator geometry. We demonstrate the code’s efficiency and robustness which is achieved through leveraging methods provided by high-performance mathematical libraries from the Julia community, such as Krylov subspace methods. Efficient evaluation of linear ideal MHD stability is crucial for stellarator optimization.

A stellarator is a nuclear fusion device that uses external non-axisymmetric coils to generate and twist a magnetic field to contain plasma particles. Stable stellarator equilibria are necessary for sustained fusion energy production, but stability evaluation is challenging because of the geometric complexity of stellarators. Ideal Magnetohydrodynamics (MHD) is a model which assumes that the plasma is a perfectly conducting fluid in an electromagnetic field. Linear ideal MHD stability describes the global behavior of the plasma. The linear ideal MHD stability problem can be expressed as a generalized eigenvalue problem involving the ideal MHD force operator.

For strongly shaped 3D configurations such as stellarators, this problem must be solved numerically. By developing a new numerical tool in Julia for evaluating global (linear) ideal MHD stability in stellarator geometry, we make a vital contribution to the process of optimizing stellarator configurations for fusion energy.

I am an applied mathematics graduate student and GEM Fellow. I currently work as a research assistant at the Princeton Plasma Physics Laboratory (PPPL). I am interested in the areas of dynamical systems, numerical analysis, and scientific computing. I am particularly drawn to applications in the areas of environmental sustainability and medicine. In Summer 2021, I interned at PPPL and developed a code using the automatic differentiation packages in Julia to optimize the design of stellarator (a nuclear fusion device) coils. I recently completed the framework of a code in Julia to solve a linear eigenvalue problem for the evaluation of the global stability of a given 3D plasma equilibrium in stellarator geometry.