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GCN Circular 22016

IceCube-171015A - IceCube observation of a high-energy neutrino candidate event
2017-10-15T14:30:35Z (7 years ago)
Erik Blaufuss at U. Maryland/IceCube <>
The IceCube Collaboration ( reports:

On 15 October, 2017 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) selection. 
The IceCube detector was in a normal operating state. HESE events have a 
neutrino vertex inside of the detector (to reduce background) and have a 
high light level (a proxy for energy).

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

Date: 2017-10-15
Time: 01:34:30.06 UT
RA: 162.86 deg (-1.70 deg / +2.60 deg 90% PSF containment) J2000
Dec: -15.44 deg (-2.00 deg / +1.60 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.

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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