Large eddy simulations of magnetized mergers of neutron stars with neutrinos

Neutron star mergers are very violent events involving extreme physical processes: dynamic, strong-field gravity; large magnetic field; very hot, dense matter; and the copious production of neutrinos. Accurate modeling of such a system and its associated multimessenger signals, such as gravitational waves, short gamma ray bursts, and kilonova, requires the inclusion of all these processes and is increasingly important in light of advancements in multimessenger astronomy generally, and in gravitational wave astronomy in particular (such as the development of third-generation detectors). Several general relativistic codes have been incorporating some of these elements with different levels of realism. Here, we extend our code mhduet, which can perform large eddy simulations of magnetohydrodynamics to help capture the magnetic field amplification during the merger, and to allow for realistic equations of state and neutrino cooling via a leakage scheme. We perform several tests involving isolated and binary neutron stars demonstrating the accuracy of the code.This work was supported by Grant No. PID2019–110301 GB-I00 funded by MCIN/AEI and by “ERDF A way of making Europe” (C. P.). This work was also supported by the NSF under Grants No. PHY-1912769 and No. PHY-2011383 (S. L. L.). Simulations were computed, in part, on XSEDE computational resources. We thankfully acknowledge the computer resources at MareNostrum and the technical support provided by the Barcelona Supercomputing Center (BSC) through grant project Long-LESBNS by the 22nd PRACE regular call (Proposal 2019215177)