Short duration gamma-ray bursts and their outflows in light of GW170817

TL;DR

This paper reviews how GW170817 has advanced understanding of short gamma-ray bursts (SGRBs), confirming their neutron star merger origin and providing detailed data that inform models of SGRB outflows and their properties.

Contribution

It synthesizes recent observational and theoretical insights from GW170817 to improve understanding of SGRB progenitors and outflows, highlighting new questions and future research directions.

Findings

Confirmed binary neutron star mergers as SGRB progenitors

Provided detailed multi-messenger data on GW170817

Enhanced understanding of SGRB outflow properties

Abstract

The detection of GW170817, it's extensive multi-wavelength follow-up campaign, and the large amount of theoretical development and interpretation that followed, have resulted in a significant step forward in the understanding of the binary neutron star merger phenomenon as a whole. One of its aspects is seeing the merger as a progenitor of short gamma-ray bursts (SGRB), which will be the subject of this review. On the one hand, GW170817 observations have confirmed some theoretical expectations, exemplified by the confirmation that binary neutron star mergers are the progenitors of SGRBs. In addition, the multimessenger nature of GW170817 has allowed for gathering of unprecedented data, such as the trigger time of the merger, the delay with which the gamma-ray photons were detected, and the brightening afterglow of an off-axis event. All together, the incomparable richness of the data from GW170817 has allowed us to paint a fairly detailed picture of at least one SGRB. I will detail what we learned, what new questions have arisen, and the perspectives for answering them when a sample of GW170817-comparable events have been studied.