Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons

TL;DR

This paper investigates how cosmogenic neutrinos and photons produced during the propagation of ultra-high-energy cosmic rays can reveal their origins, using models and observational data to constrain source properties and composition.

Contribution

It provides a comprehensive analysis of cosmogenic neutrino and photon fluxes across various models, linking them to UHECR source characteristics and observational constraints.

Findings

Most models predict detectable neutrino fluxes with current experiments.

Neutrino and photon observations can distinguish between nearby and distant UHECR sources.

Constraints on UHECR composition and source evolution are derived from messenger flux comparisons.

Abstract

We study the production of cosmogenic neutrinos and photons during the extragalactic propagation of ultra-high-energy cosmic rays (UHECRs). For a wide range of models in cosmological evolution of source luminosity, composition and maximum energy we calculate the expected flux of cosmogenic secondaries by normalizing our cosmic ray output to experimental spectra and comparing the diffuse flux of GeV-TeV gamma-rays to the experimental one measured by the Fermi satellite. Most of these models yield significant neutrino fluxes for current experiments like IceCube or Pierre Auger. Furthermore, we discuss the possibilities of signing the presence of UHE proton sources either within or outside the cosmic ray horizon using neutrinos or photons observations even if the cosmic ray composition becomes heavier at the highest energies. We discuss the possible constraints that could be brought on the UHECR origin from the different messengers and energy ranges.