WoU-MMA: Core Collapse Supernova Gravitational Wave Signature Predictions Based on 3D Models with Increasing GR Realism

Explosions of massive stars known as core collapse supernovae are responsible directly or indirectly for the lion’s share of the elements in the periodic table. A detailed understanding of how they occur is needed to understand our cosmic origins. It is known that core collapse supernovae occur under severe conditions. Very high densities of stellar material and very high velocities of this material, relative to the speed of light, are the norm. Gravity in these environments is not well described by Newton’s theory. Einstein’s theory, the so-called general theory of relativity, is needed. In fact, all core collapse supernova model components (the description of gravity, the description of the stellar core as a fluid, and the description of the radiation present in the star in the form of neutrinos, which drives these explosions) must be general relativistic. During the time period of this project, the PI will complete the development of the general relativistic descriptions of these three components. But massive stars have magnetic fields, and they, too, aid in driving their death throes. Thus, magnetic fields must be included as well. This project will allow the PI and his collaborators to extend general relativistic core collapse supernova models to include magnetic fields and, thereby, complete them. Core collapse supernovae are general relativistic. It is known, too, that magnetic fields can no longer be ignored. Models must include general relativistic gravity, magnetohydrodynamics (MHD), and spectral neutrino kinetics in the form of moments or a Boltzmann model. Under the current award, the development of solvers for general relativistic gravity and hydrodynamics in the Conformally Flat Approximation (CFA) will be completed. In addition, magnetic fields will be included, and the CFA hydrodynamics solver will be extended to MHD. One-, two-, and perhaps critical phases of three-dimensional simulations will be performed, with and without magnetic fields. Three-dimensional simulations spanning stellar mass, rotation, and metallicity will be performed with the current production simulation capability, Chimera. This project will support the analysis of the associated gravitational wave emission. Predictions for both the temporal characteristics, such as the gravitational wave strain in both polarizations, and the spectral characteristics, such as the gravitational wave spectrum and heatmaps, of the gravitational wave emission will be made. The gravitational wave data will be made available to the gravitational wave astronomy community for its use.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.