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GCN Circular 33855

AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230523A
2023-05-23T04:07:06Z (a year ago)
Hugo Ayala at Pennsylvania State University <>
The AMON,  IceCube, and HAWC collaborations report:

The AMON NuEm stream channel found a coincidence alert from the
IceCube online neutrino selection + HAWC daily monitoring analysis.
The analysis looks for IceCube neutrino events -mostly atmospheric
in origin- around the position and transit time of a HAWC cluster of
likely gamma rays, as identified in the integrated observations from
a single transit, in this case having a duration of 5.82 hours.

The HAWC transit interval starts from 2023/05/22 21:07:51 UT -
2023/05/23 02:57:2 UT
(End of the HAWC transit time)

The location of the coincidence is reported as
RA (J2000): 143.40 deg
Dec (J2000): 4.83 deg
Location uncertainty (50% containment): 0.14 deg (statistical only).
Location uncertainty (90% containment): 0.25 deg (statistical only).

The false alarm rate (FAR) of this coincidence is 0.87 per year.
We encourage follow-up observations of the alert region contingent on
the availability of resources and interest, given the quoted FAR.

AMON seeks to perform a real-time correlation analysis of the
high-energy signals across all known astronomical messengers. More
information about AMON can be found in
Information on the IceCube collaboration:
Information on the HAWC collaboration:

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