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GCN Circular 23918

IceCube-190221A - IceCube observation of a high-energy neutrino candidate event
2019-02-21T13:38:35Z (5 years ago)
Ignacio Taboada at Georgia Inst of Tech <>
The IceCube Collaboration ( reports:

On February 21st, 2019, IceCube detected a track-like, very-high-energy event with a high probability of being of astrophysical origin. The event was identified by the High Energy Starting Event (HESE) track selection. The IceCube detector was in a normal operating state. HESE tracks have a neutrino interaction vertex inside the detector and produce a muon that only partially traverses the detector volume, and have a high light level (a proxy for energy). �We encourage follow-up observations.

After the initial automated alert (, more 
sophisticated reconstruction algorithms have been applied offline, with the direction refined to:

Date: 2019/02/21 
Time: 08:25:40 UT
RA: 268.81 [-1.8,+1.2] (deg �90% PSF containment) J2000
Dec: -17.04 [-0.5,+1.3] (deg 90% PSF containment) J2000

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
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