On the Common Origin of Cosmic Rays across the Ankle and Diffuse Neutrinos at the Highest Energies from Low-luminosity Gamma-Ray Bursts

We demonstrate that the ultra-high-energy cosmic rays (UHECRs) produced in the nuclear cascade in the jets of low-luminosity gamma-ray bursts (LL-GRBs) can describe the UHECR spectrum and composition, and at the same time, the diffuse neutrino flux at the highest energies. The radiation density in the source simultaneously controls the neutrino production and the development of the nuclear cascade, leading to a flux of nucleons and light nuclei describing even the cosmic-ray ankle at 5 • 10 18 eV. The derived source parameters are consistent with population studies, indicating a baryonic loading factor of about 10. Our results motivate the continued experimental search of LL-GRBs as a unique GRB population.