Turbulent magnetic field amplification in binary neutron star mergers

Understand

Magnetic fields are expected to play a key role in the dynamics and the ejection mechanisms that accompany the merger of two neutron stars.

• General relativistic magnetohydrodynamic (MHD) simulations offer a unique opportunity to unravel the details of the ongoing physical processes.
• Nevertheless, current numerical studies are severely limited by the fact that any affordable resolution remains insufficient to fully capture the small-scale dynamo, initially triggered by the Kelvin-Helmholtz instability, and later sourced by several MHD processes involving differential rotation.
• Here, we alleviate this limitation by using explicit large-eddy simulations, a technique where the unresolved dynamics occurring at the sub-grid scales (SGS) is modeled by extra terms, which are functions of the resolved fields and their derivatives.