{
  "bibcode": "2025GCN.40153....1I",
  "circularId": 40153,
  "subject": "IceCube-250416A - IceCube observation of a high-energy neutrino candidate track-like event",
  "submittedHow": "web",
  "format": "text/plain",
  "createdOn": 1744834674359,
  "eventId": "IceCube-250416A",
  "submitter": "A. Zegarelli at Ruhr University Bochum <azegarelli@icecube.wisc.edu>",
  "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 25-04-16 at 18:32:14.97 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%.\nThis alert has an estimated false alarm rate of 2.3036 events per year due to atmospheric \nbackgrounds. The IceCube detector was in a normal operating state at the time of detection.\n\nAfter the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/140799_37236133.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:\n\nDate: 25-04-16\nTime: 18:32:14.97 UT\nRA: 83.1 (+0.57/-0.58 deg 90% PSF containment) J2000\nDec: 15.64 (+0.49/-0.5 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino.\n\nNo known gamma-ray sources listed in the Fermi 4FGL-DR4 or 3FHL catalogs are located within the 90% uncertainty region of the event.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica.\n\nThe IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu"
}