GCN 45171: IceCube-260708A: Follow-up studies of cosmic-ray origin of high-energy neutrino alert

The IceCube Collaboration (http://icecube.wisc.edu/) reports:

IceCube reported a 2.29 PeV neutrino event (https://gcn.nasa.gov/circulars/45120). We performed follow-up studies based on the timing distribution of hits inside the ice and hits in the IceTop cosmic-ray air-shower array on the surface above the in-ice part of the detector with tools that are not available for realtime selection of events yet. We find that the observed signatures are unlikely to be produced by a high-energy neutrino but instead indicate an origin in multiple muons produced in a cosmic-ray air shower, which is an expected, but rare background.