HEP@VUB meetings

In recent years, the IceCube neutrino observatory has strongly established the existence of a high energy astrophysical neutrino flux. While the existence of this neutrino flux was expected from the observation of an (ultra-high-energy) cosmic ray flux, the sources of these neutrinos are still unknown. The contribution from the prime candidate sources, gamma-ray bursts and active galactic nuclei, is by now strongly constrained, leaving us to consider other sources. In addition, the isotropic gamma-ray background measured by Fermi leads to tensions with typical models of neutrino production, which involve sources transparent to gamma-rays. This motivates us to look for a source class which is obscured in gamma rays. In this presentation, I will present the modelling of neutrino emission from a source class which is obscured by matter and where the neutrino emission happens through the pp channel.