Numerical relativity confronts compact neutron star binaries: a review and status report

TL;DR

This review discusses the progress and challenges in numerically modeling neutron star mergers and black hole-neutron star systems, emphasizing the integration of relativity and microphysics for gravitational wave and gamma-ray burst predictions.

Contribution

It provides a comprehensive overview of recent advancements in simulating NSNS and BHNS mergers, highlighting the integration of complex physics for accurate modeling.

Findings

Improved modeling of gravitational wave signals from mergers.

Enhanced understanding of post-merger dynamics and gamma-ray burst origins.

Progress in combining relativity with microphysics in simulations.

Abstract

We review the current status of attempts to numerically model the merger of neutron star-neutron star (NSNS) and black hole-neutron star (BHNS) binary systems, and we describe the understanding of such events that is emerging from these calculations. To accurately model the physics of NSNS and BHNS mergers is a difficult task. It requires solving Einstein's equations for dynamic spacetimes containing black holes. It also requires evolving the hot, supernuclear-density neutron star matter together with the magnetic and radiation fields that can influence the post-merger dynamics. Older studies concentrated on either one or the other of these challenges, but now efforts are being made to model both relativity and microphysics accurately together. These NSNS and BHNS simulations are then used to characterize the gravitational wave signals of such events and to address their potential for generating short-duration gamma ray bursts.