Core Collapse Supernova Gravitational Wave Signature Predictions Based on 3D Ab Initio Models with Increasing GR Realism

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

Core Collapse Supernovae (CCSN) are catastrophic events that mark the death of massive stars and these violent explosions are responsible for most of the elements in the Periodic Table. The theory of gravity developed by Newton is not sufficient to describe the extreme densities in the CCSN mechanism. As such, CCSN represent an excellent test bed for Einstein's theory of gravity. This project will advance the description of gravity in current CCSN models, from an essentially Newtonian description with a simple correction accounting for some Einsteinian effects to a far more sophisticated approximation of Einsteinian gravity, thereby improving significantly the realism of future CCSN studies. The new models will be used to make predictions for the emission of gravitational waves, ripples in the fabric of space-time, in core collapse supernovae. Such supernovae are among the three primary sources that will produce gravitational waves detectable by the Laser Interferometric Gravitational Wave Observatory (LIGO). The PI will work closely with members of the LIGO Collaboration to develop new tools for LIGO data analysis. This project will train a graduate student in CCSN theory and gravitational wave astronomy and will provide a research opportunity for an intern in the Fisk-Vanderbilt Ph.D. program. Advanced multi-physics models of core collapse supernovae that include multi-frequency neutrino transport with a complete set of neutrino weak interactions and key relativistic corrections such as gravitational redshift, have implemented to date only an effective self-gravitational potential, which is computed using the Newtonian potential obtained by solving the Poisson equation with a correction to the monopole term. The latter is determined from an integral formulation of the Tolman-Oppenheimer-Volkoff equation using angle-average densities. More realistic CCSN models require more sophisticated treatments of the general relativistic gravity. In this project, the PI and his students will implement the Conformally Flat Approximation in CCSN models. This approximation has been shown to describe well general relativistic gravity in systems without rapid rotation or black hole formation, suitable for most CCSN studies. The new models will be used to compute the emission of gravitational radiation in CCSN models using the weak-field, slow-motion approximation and will provide new gravitational wave data to the gravitational wave astronomy community.