TITLE: GCN CIRCULAR NUMBER: 33244 SUBJECT: IceCube-230201A - IceCube observation of a high-energy neutrino candidate track-like event DATE: 23/02/01 12:49:02 GMT FROM: Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 2023-02-01 at 06:20:54.42 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 for Bronze alerts is 30%. This alert has an estimated false alarm rate of 2.07 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 (https://gcn.gsfc.nasa.gov/notices_amon_g_b/137603_30799022.amon) more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2023-02-01 Time: 06:20:54.42 UT RA: 345.41 (+2.50/-3.07 deg 90% PSF containment) J2000 Dec: +12.10 (+1.62/-1.53 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. Three gamma-ray sources listed in the 4FGL Fermi-LAT catalog are located within the 90% containment region. The sources are 4FGL J2256.7+1307, 4FGL J2308.9+1111 and 4FGL J2252.6+1245, located 1.6, 2.0 and 2.3 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 roc@icecube.wisc.edu