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GCN Circular 33855

AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230523A
2023-05-23T04:07:06Z (16 days 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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