General information
IceCube-260827A is a track-like high-energy neutrino candidate detected by IceCube on 2026-08-27 at 15:35:36.97 UT and selected by the ICECUBE_Astrotrack_GOLD alert stream. The refined position is RA 86.31 deg and Dec 8.12 deg J2000, with an atmospheric-background false alarm rate of 1.134 events per year.
Wavelength coverage
- Neutrino: IceCube detected the alert event and searched for additional track-like muon neutrino events in 1000 s and 2 day windows, finding zero additional events with p-value 1.00 in both searches.
- Gamma-ray: Fermi-LAT analyzed the region and found no cataloged FL16Y gamma-ray source and no significant >5 sigma new >100 MeV excess within the 90% localization.
- Optical: ZTF observed in g and r starting about 20.2 hours after the event, covering 89.8% of the localization to typical depth 21.0 mag, and detected no candidate counterparts.
No observations are mentioned for X-ray, radio, gravitational-wave, infrared, ultraviolet, or submillimeter bands.
Lightcurve and spectrum
- IceCube 1000 s search: zero additional track-like events, p-value 1.00, E^2 dN/dE sensitivity at 1 TeV of 1.3e-01 GeV cm^-2 for an E^-2.5 spectrum.
- IceCube 2 day search: p-value 1.00, E^2 dN/dE sensitivity at 1 TeV of 1.5e-01 GeV cm^-2 for an E^-2.5 spectrum.
- IceCube reports that 90% of detectable events from a source at this declination with an E^-2.5 spectrum have energies approximately between 3e+02 GeV and 1e+05 GeV.
- Fermi-LAT 95% confidence >100 MeV flux upper limits are <2.0e-10 ph cm^-2 s^-1 for ~18 years, <9.5e-09 ph cm^-2 s^-1 for 1 month before T0, and <1.6e-07 ph cm^-2 s^-1 for 1 day before T0, assuming photon index 2.0.
- ZTF exposures were 300 s with typical depth 21.0 mag.
Redshift
What’s special vs typical