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GCN Circular 33870

IceCube-230524A - IceCube observation of a high-energy neutrino candidate track-like event
2023-05-24T13:50:23Z (15 days ago)
Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum <>
The IceCube Collaboration ( reports: On 2023-05-24 at 11:09:36.24 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_Bronze alert stream. The average astrophysical neutrino purity Bronze alerts is 30%. This alert has an estimated false alarm rate of 4.25 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection. After the initial automated alert (, more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2023-05-24 Time:  11:09:36.24 UT RA: 318.43 (+3.12 / -2.59 deg  90% PSF containment) J2000 Dec: +2.84 (+2.55 / -2.43 deg 90% PSF containment) J2000 We encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino. Two gamma-ray sources listed in the 4FGL Fermi-LAT catalog are located within the 90% uncertainty region. The sources are 4FGL J2110.3+0404 and 4FGL J2109.6+0440 located 1.50 and 2.10 deg away from the best-fit position, respectively. 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
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