Search for gravitational-wave signals associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo

The LIGO Scientific Collaboration, The Virgo Collaboration, additional authors

Published 2019-07-02Version 1

We present the results of targeted searches for gravitational wave transients associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo, which took place from November 2016 to August 2017. We have analyzed 98 gamma-ray bursts using an unmodeled search method that searches for generic transient gravitational waves and 42 with a modeled search method that targets compact-binary mergers as progenitors of short gamma-ray bursts. Both methods clearly detect the previously reported binary merger signal GW170817, with p-values of $<9.38 \times 10^{-6}$ (modeled) and $3.1 \times 10^{-4}$ (unmodeled). We find no evidence of associated gravitational-wave signals for any of the other gamma-ray bursts analyzed, and therefore report lower bounds on the distance to each of these, assuming various source types and signal morphologies. Using our final modeled search results, short gamma-ray burst observations, and assuming binary neutron star progenitors, we place bounds on the rate of short gamma-ray bursts as a function of redshift for $z \leq 1$ and estimate 0.07-1.80 detections for the 2019-20 LIGO-Virgo observing run and 0.15-3.90 joint detections per year when current gravitational-wave detectors are operating at design sensitivities.