Binary neutron star and short gamma-ray burst simulations in light of GW170817

TL;DR

This paper reviews numerical simulations of binary neutron star mergers and short gamma-ray burst jets, emphasizing their role in understanding multi-messenger astrophysics following GW170817.

Contribution

It provides a comprehensive comparison of numerical relativity simulations with short GRB jet models, highlighting established facts and areas needing further research.

Findings

Simulations have advanced understanding of BNS mergers and jet formation.

There are known aspects of jet propagation through ejecta.

Certain assumptions in models require revision for accuracy.

Abstract

In the dawn of the multi-messenger era including gravitational waves, which was marked by the first ever coincident detection of gravitational waves and electromagnetic radiation it is important to lay back and think about established knowledge. Numerical simulations of binary neutron star mergers and simulations of short GRB jets have to combine efforts in order to understand such complicated and phenomenologicaly rich explosions. We review the status of numerical relativity simulations with respect to any jet or magnetized outflow produced after merger. We compare what is known from such simulations, with what is used and obtained from short GRB jet simulations propagating through the BNS ejecta. We point out facts that are established and can be considered known, and things that need to be further revised and/or clarified.