GCN Circular 32475
Subject
IceCube-220822A - IceCube observation of a high-energy neutrino candidate track-like event
Date
2022-08-22T23:07:55Z (2 years ago)
From
Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum <lincetto@astro.rub.de>
The IceCube Collaboration (http://icecube.wisc.edu/) reports:
On 2022-08-22 20:26:30.03 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 2.005 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/136973_28816141.amon) more
sophisticated reconstruction algorithms have been applied offline, with
the direction refined to:
Date: 2022-08-22
Time: 20:26:30.03 UT
RA: 273.08 (+2.47, -2.50 deg 90% PSF containment) J2000
Dec: +21.54 (+0.94, -1.18 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.
Two gamma-ray sources listed in the 4FGL Fermi-LAT catalog are located
in the 90% containment region. The sources are 4FGL J1809.3+2042 and
4FGL J1819.1+2133 (3FHL J1819.2+2135), respectively located at 1.08 and
1.58 deg 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