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GCN Circular 24378

IceCube-190503A - IceCube observation of a high-energy neutrino candidate event
2019-05-03T20:51:47Z (5 years ago)
Erik Blaufuss at U. Maryland/IceCube <>
The IceCube Collaboration ( reports:

On 19/05/03 at 17:23:08 UT IceCube detected a track-like, 
very-high-energy event with a high probability of being of astrophysical 
origin. The ��event was identified by the Extremely High Energy (EHE) 
track event selection.�� The IceCube detector was in a normal operating 
state.�� EHE events typically have a neutrino interaction vertex that is 
outside the detector, produce a muon that traverses the detector volume, 
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: 19/05/03
Time: 17:23:08.72 UT
RA: 120.28 (+0.57 -0.77 deg ��90% PSF containment) J2000
Dec: 6.35 (+0.76 -0.70 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% region. The 
nearest known gamma-ray source is 4FGL J0800.9+0733 at RA: 120.2262 deg, 
Dec: 7.5509 deg (1.2 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
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