RUI: Cross-Validation of Binary Neutron Star Mergers Simulations across Multiple Codes

Binary neutron star mergers are extraordinary astrophysical events that provide critical insights into fundamental physics. However, accurately simulating these complex phenomena remains challenging due to uncertainties in numerical methods and the physical processes involved. This project addresses these challenges by developing a systematic approach to validating and improving binary neutron star simulations. By actively engaging undergraduate and master's students in computational astrophysics, this initiative advances scientific knowledge, enhances education, and benefits society through outreach and public engagement. This work will cross-validate results from multiple numerical relativity codes by performing convergence analyses and using analytical quasi-universal relations connecting gravitational wave frequencies and equations of state to evaluate code accuracy and identify areas needing refinement. It will systematically compare binary neutron star mergers simulations across a range of mass ratios, individual neutron star spins, magnetic field strengths, and neutrino physics to determine their effects on gravitational wave signals and matter ejected during mergers. The results will assess how these physical factors influence disk mass, ejecta velocity, and angular distribution, all critical for understanding observed electromagnetic signals, such as kilonovae. 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.