Astrophysical neutrino production and impact of associated uncertainties in photo-hadronic interactions of UHECRs

Understand

High energy neutrinos can be produced by interactions of ultra-high energy cosmic rays (UHECRs) in the dense radiation fields of their sources as well as off the cosmic backgrounds when they propagate through the universe.

• Multi-messenger interpretations of current measurements deeply rely on the understanding of these interactions.
• In order to efficiently produce neutrinos in the sources of UHECRs, at least a moderate level of interactions is needed, which means that a nuclear cascade develops if nuclei are involved.
• On the other hand, the available cross-section data and interaction models turn out to make poor predictions for most nuclei heavier than protons.