TeV to PeV neutrinos from radio-bright blazars

Observational information on high-energy astrophysical neutrinos is being continuously collected by the IceCube observatory. However, their sources were still unknown. We adress the problem of the astrophysical neutrinos' origin in a statistical manner. It is found that AGNs positionally associated with IceCube events have typically stronger parsec-scale cores than the rest of the sample. The probability of a chance coincidence is $4\times10^{-5}$ corresponding to a significance of $4.1\sigma$. We select five strong blazars as highly probable associations for neutrinos above 200 TeV: 3C 279, NRAO 530, TXS 1308+326, PKS 1741-038, and PKS 2145+067. There are at least 70 more bright AGNs that emit neutrinos of lower energies starting from TeVs. Moreover, we find radio flares at frequencies above 10 GHz around neutrino arrival times for several VLBI-selected AGN on the basis of RATAN-600 monitoring. The most pronounced example of such behavior is PKS 1502+106. We conclude that AGNs with bright Doppler-boosted jets may explain the entire IceCube astrophysical neutrino flux as derived from muon-track analyses. High-energy neutrinos can be produced in parsec-scale AGN jets in interactions of relativistic protons with self-Compton photons, or photons emitted close to the accretion disk. Radio-bright blazars associated with neutrinos have very diverse gamma-ray properties suggesting that gamma-rays and neutrinos may be produced in different regions of AGN and not directly related. A small jet viewing angle is, however, required to detect either of them.