GCN Circular 33040

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

On 22-12-10 at 08:35:11.23 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 0.9539 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/137350_7930341.amon), more
sophisticated reconstruction algorithms have been applied offline, with
the direction refined to:

Date: 22-12-10
Time: 08:35:11.23

RA: 332.58 (+9.84/-11.77 deg  90% PSF containment) J2000
Dec: +22.75 (+8.15/-4.13 deg 90% PSF containment) J2000

Due to the event being a short through-going track, the 90% uncertainty
contour is especially large.

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 2 deg of the best-fit candidate neutrino position. The sources
are 4FGL J2207.1+2222 and 4FGL J2212.0+2356, and are located 0.82 and
1.25 deg away from the best-fit position, respectively. A total of 20
sources listed in the 4FGL catalog are within the 90% containment
radius of the event.

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