GCN Circular 34527

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

On 2023-08-23 at 08:26:14.59 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 0.5131 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/138283_14780365.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:

Date: 2023-08-23
Time:  08:26:14.59 UT
RA: 17.93 (+0.36, -0.38 deg  90% PSF containment) J2000
Dec: -12.10 (+0.23, -0.24 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 4FGL-DR4 or 3FHL catalog sources in the 90% uncertainty region of the event. The nearest gamma-ray source in either catalog is 4FGL J0110.7-1254 at RA: 17.69 deg, Dec: -12.91 deg (0.84 deg away from the best-fit alert 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