Nuclear Astrophysics approaching the Exascale: Multi-physics simulations of stellar explosions and their nucleosynthesis

Multi-physics simulations of stellar explosions (such as supernovae and neutron star mergers) are one of the most important avenues available to address fundamental questions in nuclear astrophysics, such as the cosmic origin of the elements, the behavior of matter and neutrinos at extreme densities, the structure and evolution of compact objects, and the sources of gravitational waves.

ExaStar is an application development project within DOE's Exascale Computing Project (ECP). ExaStar is working to deliver an efficient, versatile, and portable code suite for multi-physics astrophysics simulations run on exascale machines. The project builds on the capabilities of current simulation codes (including FLASH and Castro), is based on the adaptive mesh refinement framework AMReX, and will include modules for hydrodynamics, spectral radiation (neutrino) transport, nuclear reactions, and microphysics. This presentation will outline recent progress towards understanding some of the aforementioned nuclear astrophysics questions that has been enabled by ExaStar development, as well as providing a description of what we hope to learn at the exascale.