GCN Circular 28504

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

On 20/09/26 at 07:54:11.62 UT IceCube detected a track-like event with a high probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_Gold alert stream. The average astrophysical neutrino purity for Gold alerts is 50%. This alert has an estimated false alarm rate of 0.536 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/134533_53384881.amon), more 
sophisticated reconstruction algorithms have been applied offline, with the direction refined to:

Date: 20/09/26
Time: 07:54:11.62  UT
RA: 96.46 (+ 0.73 - 0.55  deg 90% PSF containment) J2000
Dec: -4.33 (+ 0.61  - 0.76  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.

There are no Fermi-LAT 4FGL or 3FHL sources inside the 90% localization region. The closest source is 4FGL J0613.7-0201 located at RA 93.44 deg and Dec -2.02 deg (J2000), at a distance of 3.8 degrees from the best-fit location.

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