General information
IceCube-260825A is a track-like IceCube high-energy neutrino candidate detected on 2026-08-25 at 10:53:33.63 UT and selected by the ICECUBE_Astrotrack_BRONZE alert stream. The refined position is RA 91.95 deg, Dec 45.73 deg, with a reported atmospheric-background false alarm rate of 0.5733 events per year.
Wavelength coverage
- Neutrino: IceCube reported the original track-like alert and later searched for additional track-like muon neutrino events in 1000 s and 2-day windows.
- Optical: ZTF observed in g and r bands starting about 0.1 hours after the event, covering 81.2% of the reported localization region to a typical depth of 21.0 mag, with no candidate counterparts detected.
- Gamma-ray: Fermi-LAT searched the region above 100 MeV and found no significant new excess and no cataloged FL16Y gamma-ray source within the 90% localization.
No observations are mentioned in X-ray, radio, infrared, ultraviolet, gravitational-wave, or TeV gamma-ray bands.
Lightcurve and spectrum
- IceCube additional-neutrino search: zero additional track-like events were found within the 90% containment region in the 1000 s window, with p-value 1.00.
- IceCube 2-day search: p-value 0.03, reported as consistent with no significant excess of track events.
- IceCube sensitivity for an E^-2.5 spectrum: E^2 dN/dE at 1 TeV of 1.5e-01 GeV cm^-2 in 1000 s and 1.8e-01 GeV cm^-2 in 2 days.
- Fermi-LAT assumed a fixed photon index of 2.0 for a point source at the IceCube best-fit position and reported >100 MeV 95% flux upper limits of <1.8e-10 ph cm^-2 s^-1 for ~18 years, <5.2e-09 ph cm^-2 s^-1 for 1 month before T0, and <1.1e-07 ph cm^-2 s^-1 for 1 day before T0.
Redshift
What’s special vs typical