Neutrinos from blazar jets: beaming is the key

We present a joint analysis of IceCube neutrino events and radio observations of active galaxies, where we found a significant (> 3.5 sigma) association between high-energy neutrinos and radio-bright blazars. Observationally, we find neutrinos at TeV-PeV energies to be predominantly detected from blazars with jets pointed towards the Earth. This connection indicates that neutrinos are beamed similarly to the electromagnetic radiation, with the neutrino beaming caused by the proton bulk motion along the jet. Blazars are a significant source of neutrinos together, as a sample; still, individual sources contribute less than one detected neutrino on average. Hints for neutrinos from blazars have been recently detected by ANTARES/KM3Net and Baikal-GVD, highlighting the importance of multiple observatories for reliable joint studies in the near future.