Code Dependence of Sedov–Taylor Supernova Remnant Evolution: FLASH, Athena, and RAMSES

Supernovae play a crucial role in the self-regulation of star-forming galaxies: supernova remnants disrupt giant molecular clouds, curtailing star formation in open clusters, and supernova-deposited momentum drives galactic outflows. The energy-conserving Sedov–Taylor phase captures the transfer of momentum from the expanding remnant to the interstellar medium. However, Eulerian grid codes suffer advective losses that may impact momentum deposition, depending on the numerical technique. We performed three-dimensional magnetohydrodynamic simulations comparing remnant expansion in FLASH, Athena, and RAMSES, varying density, adiabatic index and numerical resolution, and toggling a uni-directional magnetic field. We find a maximum relative difference of ∼30%, decreasing with resolution. However, since state-of-the-art isolated galaxy simulations resolve the Sedov–Taylor phase with 8–16 grid cells, substantial differences may persist between codes.