GCN Circular 28433
Subject
IceCube-200916A - IceCube observation of a high-energy neutrino candidate track-like event
Date
2020-09-16T22:20:38Z (4 years ago)
From
Erik Blaufuss at U. Maryland/IceCube <blaufuss@umd.edu>
The IceCube Collaboration (http://icecube.wisc.edu/) reports:
On 20/09/16 at 20:40:30.95 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 threshold astrophysical neutrino purity for Bronze alerts is 30%. This alert has an estimated false alarm rate of 2.48 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/134498_12605830.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:
Date: 20/09/16
Time: 20:40:30.95 UT
RA: 109.78 +1.08 -1.44 (deg 90% PSF containment) J2000
Dec: 14.36 +0.88 -0.85 (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 or 3FHL catalog sources in the 90% uncertainty region. The nearest gamma-ray source in either catalog is 4FGL J0725.2+1425, associated with the BL Lac object 4C +14.23, at RA: 111.32 deg, Dec: 14.42 deg (1.50 deg away from the best-fit event 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