thornado-GRMHD: Module Development, Testing, and Application to General Relativistic Models of the Magneto-Rotational Instability in Core-Collapse Supernovae

Core-collapse supernovae (CCSNe) are astronomical events influenced by physical processes on widely different spatial and temporal scales, making our understanding of them dependent on simulation. Furthermore, the simulation codes themselves must be extendable with new physics modules, while still remaining performant at the exascale and beyond. To this end, we are developing the multi-physics toolkit for high-order neutrino radiation hydrodynamics (thornado), which makes use of the promising performance benefits of both Galerkin methods and adaptive mesh refinement (provided by the AMReX framework). Here, we report on the development and testing of the solution module for the equations of ideal, general relativistic magnetohydrodynamics (GRMHD), with a focus on features, such as the use of divergence cleaning to maintain physicality of the magnetic field, that make it unique compared to our GRHD solution module. We also report on the status of our first science objective: an extension of the non-relativistic, shearing disk model (originating in Obergaulinger et al., A&A 498, 241–271, 2009) of the magneto-rotational instability in CCSNe to a GRMHD-equivalent on a static, Schwarzschild spacetime.