SIMSOPT: A flexible framework for stellarator optimization

A stellarator is a magnetic field configuration used to confine plasma, and it is a candidate configuration for fusion energy, as well as a general charged particle trap.A stellarator's magnetic field is typically produced using electromagnetic coils, and the shaping of the field and coils must be optimized to achieve good confinement.SIMSOPT is a collection of software components for carrying out these optimizations.These components include • Interfaces to physics codes, e.g. for magnetohydrodynamic (MHD) equilibrium.• Tools for defining objective functions and parameter spaces for optimization.• Geometric objects that are important for stellarators -surfaces and curves -with several available parameterizations.• Implementations of the Biot-Savart law and other magnetic fields, including derivatives.• Tools for parallelized finite-difference gradient calculations.