TITLE:   GCN CIRCULAR
NUMBER:  34170
SUBJECT: IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
DATE:    23/07/08 12:32:13 GMT
FROM:    Massimiliano Lincetto at Ruhr-Universitaet Bochum <lincetto@astro.ruhr-uni-bochum.de>

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

On 23-07-08 at 08:17:05.21 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 0.9371 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/138131_35302784.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:

Date: 23-07-08 
Time: 08:17:05.21 UT
RA: 270.70 (+3.72 / -4.72 deg  90% PSF containment) J2000
Dec: -8.46 (+2.54 / -2.41 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 Fermi 4FGL-DR3 or 3FHL catalog sources are located in the 90% uncertainty region. The sources are 4FGL J1755.9+0953, 4FGL J1805.6+0615 (PSR J1805+0615) and 3FGL J1751.5+0939 (OT 081) respectively located at 2.22, 2.32 and 3.03 deg away from the best-fit 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