Compact object coalescence rate estimation from short gamma-ray burst observations

TL;DR

This paper estimates the local universe merger rate of compact binary systems from short gamma-ray burst observations and predicts the expected coincident detection rate with gravitational-wave signals.

Contribution

It provides a new estimate of the compact binary merger rate based on SGRB data and forecasts coincident detection rates with gravitational waves.

Findings

Merger rate estimated at 500-1500 Gpc$^{-3}$yr$^{-1}$

Expected coincident GW-SGRB observations are 0.2 to 1 per year

Results align with previous estimates and models

Abstract

Recent observational and theoretical results suggest that Short-duration Gamma-Ray Bursts (SGRBs) are originated by the merger of compact binary systems of two neutron stars or a neutron star and a black hole. The observation of SGRBs with known redshifts allows astronomers to infer the merger rate of these systems in the local universe. We use data from the SWIFT satellite to estimate this rate to be in the range $\sim 500$-1500 Gpc$^{-3}$yr$^{-1}$. This result is consistent with earlier published results which were obtained through alternative approaches. We estimate the number of coincident observations of gravitational-wave signals with SGRBs in the advanced gravitational-wave detector era. By assuming that all SGRBs are created by neutron star-neutron star (neutron star-black hole) mergers, we estimate the expected rate of coincident observations to be in the range $\simeq 0.2$ to 1 ($\simeq 1$ to 3) yr$^{-1}$.