Near-future discovery of point sources of ultra-high-energy neutrinos

Abstract

Upcoming neutrino telescopes may discover ultra-high-energy (UHE) cosmic neutrinos, with energies beyond 100 PeV, in the next 10-20 years. Their sources are guaranteed interactions sites of UHE cosmic rays. We propose to identify sources via search of multiplets of UHE neutrinos from similar directions. We provide state-of-the-art forecasts of their detection in the radio array of IceCube-Gen2. We find that sources at declination of −45 • to 0 • will be easiest to discover. Discovering even one steady-state source in 10 years would imply that the source has an UHE neutrino luminosity at least larger than about 10 43 erg s −1 (depending on the source redshift evolution). Discovering no transient source would disfavor transient sources brighter than 10 53 erg as dominant.