Skip to main content
U.S. flag

An official website of the United States government

GCN Circulars are now part of the new GCN! See news and announcements

GCN Circular 33850

LIGO/Virgo/KAGRA S230522a: 2 counterpart neutrino candidates from IceCube neutrino searches
2023-05-22T12:26:35Z (17 days ago)
Jessie Thwaites at IceCube/U Wisc-Madison <>
IceCube Collaboration ( reports: A search for track-like muon neutrino events detected by IceCube consistent with the sky localization of gravitational-wave candidate S230522a in a time range of 1000 seconds centered on the alert event time (2023-05-22 09:29:45.000 UTC to 2023-05-22 09:46:25.000 UTC) have been performed [1,2]. During this time period IceCube was collecting good quality data. The search is a maximum likelihood analysis which searches for a generic point-like neutrino source coincident with the given GW skymap. 2 track-like event(s) are found in spatial and temporal coincidence with the gravitational-wave candidate S230522a calculated from the map circulated in the 2-Preliminary notice. This represents an overall p-value of 0.04 (1.8 sigma). These p-values measure the consistency of the observed track-like events with the known atmospheric backgrounds for this single map (not trials corrected for multiple GW events). The most probable multi-messenger source direction based on the neutrinos and GW skymap is RA 78.93, dec -37.54 degrees. The false alarm rate of these coincidences can be obtained by multiplying the p-values with their corresponding GW trigger rates. Properties of the coincident events are shown below. dt ra dec Angular Uncertainty(deg) p-value(generic transient) p-value(Bayesian) ----------------------------------------------------------------------------------------------------- -152.13 78.98 -37.59 0.43 0.04 n/a 73.08 127.79 -8.33 0.43 0.09 n/a where: dt = Time of track event minus time of GW trigger (sec) Angular uncertainty = Angular uncertainty of track event: the radius of a circle representing 90\% CL containment by area. p-value = the p-value for this specific track event from each search. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at [1] M. G. Aartsen et al 2020 ApJL 898 L10 [2] Abbasi et al. Astrophys.J. 944 (2023) 1, 80
Looking for U.S. government information and services? Visit