Binary neutron star mergers using the GRHayL-based IllinoisGRMHD*

The numerical relativity community has developed a wide range of tools for simulating astrophysical systems using general relativistic magneto-hydrodynamics (GRMHD). Despite the availability of these simulation codes, the lack of modularity and interoperability poses challenges for collaborative efforts, especially in open-source projects that rely on community contributions. To address this problem, we have developed the General Relativistic Hydrodynamics Library (GRHayL) to facilitate the development, maintenance, and enhancement of GRMHD codes across multiple infrastructures.

GRHayL is a modular, infrastructure-agnostic library designed from refactoring the IllinoisGRMHD code, including the enhancements developed by Werneck et al. Many elements of the code have also been streamlined and improved during the library's development. This library serves as the foundation for codes in the Einstein Toolkit (both Carpet and CarpetX) and BlackHoles@Home infrastructures. In the previous year, we presented preliminary results regarding binary neutron star (BNS) merger simulations. We now present the final BNS comparison results with the original IllinoisGRMHD code, as well as discussion of improvements over the progenitor code. Finally, we discuss ongoing work and future plans.