The search for astrophysical neutrinos from gravitational wave sources in real time with IceCube

An electromagnetic counterpart was identified for the first binary neutron star merger detected in gravitational waves (GW 170817) , and a gamma-ray blazar (TXS 0506+056) was identified in coincidence with astrophysical neutrinos. The search is on for the third leg of the multi-messenger triangle: a possible neutrino counterpart to gravitational waves. The IceCube Neutrino Observatory responds rapidly to LIGO/Virgo Open Public Alerts by searching for neutrinos coincident in time and direction with gravitational wave alerts. Detection of a neutrino in coincidence with a gravitational wave source would revolutionize our understanding of both gravitational wave progenitors and astrophysical neutrinos. Doing so in real time would furthermore provide a localization region orders of magnitude smaller than typical gravitational wave regions, in order to quickly search for electromagnetic counterparts. We report results from LIGO/Virgo observing runs O1 and O2 as well as real-time results from O3 to date.