GCN Circular 31551

The IceCube Collaboration (http://icecube.wisc.edu/) reports:

On 2022-02-05 at 00:22:39.74 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 2.524 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection.

Due to a technical issue, the automated GCN notice for this event could not be circulated. More sophisticated reconstruction algorithms have been applied offline, with the direction refined to:

Date: 2022-02-05 
Time:  00:22:39.74 UTC
RA: 216.12 (+2.94, -3.52 deg  90% PSF containment) J2000
Dec: 15.56 (+3.26, -2.65 deg 90% PSF containment) J2000
Initial signal probability: 32.2%
Initial neutrino energy: 109.6 TeV

We encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino.

There are two Fermi 4FGL catalog sources in the 90% uncertainty region: 4FGL J1424.6+1447 and 4FGL J1428.1+1629. The nearest source is 4FGL J1424.6+1447 at RA: 216.17 deg, Dec: 14.78 deg in J2000 coordinates (0.78 deg away from the best-fit event position).

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