LAPS discretization and solution of plasma equilibrium

LAPS provides spectral element discretization for solving steady state plasma profiles. Our initial focus is on its implementation for two dimensional open magnetic field equilibria in linear and toroidal geometries. The linear geometry is an axisymmetric magnetic mirror with anisotropic pressure. The toroidal case is a tokamak scrape-off layer plasma. Structured grids are produced by the grid generation package in LAPS. The spectral element discretization uses modal bases over quadrilateral elements. A Newton-Krylov solver implemented with the Portable, Extensible Toolkits for Scientific Computing PETSc is applied to iteratively converge the solution. Care has been taken in the code design to separate the grid generation, spectral element discretization, and (non)linear solver from the user-specified equilibrium equations, so the LAPS infrastructure can be easily used for different applications.