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GCN Circular 24981

IceCube-190704A - IceCube observation of a high-energy neutrino candidate event
2019-07-04T20:49:46Z (5 years ago)
Marcos Santander at U. Alabama/IceCube <>
The IceCube Collaboration ( reports:

On 19/07/04 at 18:48:52.25 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 1.00 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 (, more
sophisticated reconstruction algorithms have been applied offline, with the direction refined to:

Date: 19/07/04
Time: 18:48:52.25 UT
RA: 161.85 (+2.16 -4.33 deg  90% PSF containment) J2000
Dec: 27.11 (+1.81 -1.83  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 is one unassociated Fermi 4FGL source lying within the 50% uncertainty region, 4FGL J1049.8+2741, at RA: 162.46 deg, Dec: 27.68 deg (0.8 deg away from the best-fit event position). There are no other Fermi 3FHL or 4FGL catalogue sources within the 90% contour.

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<>

Marcos Santander
Assistant Professor
Department of Physics & Astronomy
317B Gallalee Hall
University of Alabama
Tuscaloosa, AL 35487
+1 (205) 348 4863
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