Detecting prompt and afterglow jet emission of gravitational wave events from LIGO/Virgo/KAGRA and next generation detectors

TL;DR

This study assesses the detectability of jet emissions from binary neutron star mergers in gravitational wave events using current and future observatories, highlighting potential detection rates of afterglows and prompt emissions.

Contribution

It provides a comprehensive analysis of how various parameters influence the likelihood of detecting electromagnetic counterparts with next-generation GW detectors and telescopes.

Findings

Few O5 GW events may have detectable afterglows, mainly with SKA and JWST.

Hundreds of XG GW events could have detectable afterglows across multiple wavelengths.

Detection of prompt emission is limited in O5 but significantly increases in the XG era.

Abstract

Following the wealth of new results enabled by multimessenger observations of the binary neutron star (BNS) merger GW170817, the next goal is increasing the number of detections of electromagnetic (EM) counterparts to gravitational wave (GW) events. We study the detectability of the prompt emission and afterglows produced by the relativistic jets launched by BNS mergers that will be detected by LIGO-Virgo-KAGRA during their fifth observing run (O5), and by next generation (XG) GW detectors (Einstein Telescope and Cosmic Explorer). We quantify the impact of various BNS merger and jet afterglow parameters on the likelihood of detection, focusing on the impact of the observer's viewing angle and the jet's core half-opening angle. We explore detectability over a wide range of current state-of-the-art facilities (e.g., the James Webb Space Telescope, Chandra X-ray Observatory) as well as upcoming next-generation facilities (e.g., AXIS, NewAthena, ngVLA, SKA). We find that a few GW events (~0-4) per year may have a detectable afterglow component in O5, with the largest detection rates expected with SKA in the radio and JWST in the near-infrared. In the XG era, hundreds of multimessenger detections of afterglows per year may be possible with a range of instruments, such as NewAthena in the X-ray and ngVLA in the radio. While zero to a few GW events per year are expected to be accompanied by a detectable prompt emission in O5, dozens per year may be detectable in XG.