Simulating Core-Collapse and Electron-Capture Supernovae: from the Central Engine to the Supernova Remnant

Core-collapse supernovae, the culmination of the lives of massive stars, are the principle actors in the story of our elemental origins. Our understanding of these events centers around a stalled explosion brought back to life by a neutrinos streaming from the newly-formed neutron star. This award will support two projects to improve our understanding of the impact that the turbulent, neutrino-driven nature of supernova explosions has on observations of supernovae and galactic chemical evolution and the elemental history of our Galaxy. First, the PI will seek to investigate the explosions that result from the lightest stars to produce supernovae, those with cores composed initially of oxygen and neon, with much greater fidelity than has previously been achieved. Second, the investigator team will continue our prior project to determine the full range of nucleosynthesis products in the ejecta as realistically as possible within our simulations of the central engine of core-collapse supernovae and then extend these models of core-collapse supernovae beyond the initial epoch where the explosion is formed. To compare with observations, the PI will extend these simulations to the epoch when the shock reaches the surface of the star and the visible supernova is born.

Core-collapse supernovae, including the collapse of iron-cored stars, but also the collapse of less massive stars with oxygen and neon cores as electron capture supernovae, are the principle drivers of galactic chemical evolution. Our understanding of both of these events, while still incomplete, centers around a neutrino-driven central engine which is highly hydrodynamically unstable. Though the stalled shock is brought back to life by neutrino heating, the development of the supernova explosion is inextricably linked to three-dimensional fluid flows. Regrettably, this is ignored in most studies of supernova nucleosynthesis. This award supports two projects to improve our understanding of the impact that the turbulent, neutrino-driven nature of supernova explosions has on observations of supernovae and galactic chemical evolution. First, the investigator team will investigate the explosions that result from electron capture supernovae with much greater fidelity than has heretofore been achieved. Second, the investigator team will continue a prior project to realistically examine the full range of nucleosynthesis products that may be observed in the ejecta by extending state-of-the-art core-collapse supernova models to the epoch when the shock reaches the surface of the star and the supernova is born.

This project advances the objectives of 'Windows on the Universe: the Era of Multi-Messenger Astrophysics', one of the 10 Big Ideas for Future NSF Investments.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.