  Some generalizations of the relation between high-energy astrophysical
neutrino and cosmic ray fluxes are obtained, taking into account present
results on the cosmic ray spectrum and composition as well as a more realistic
modeling of the Galactic and extragalactic cosmic ray components down to PeV
energies. It is found that the level of neutrino fluxes measured by IceCube can
be consistent with sources that are thin to escaping protons. This could also
make it easier for heavier nuclei to be emitted from the sources without
suffering excessive disintegration processes.

High Energy Astrophysical Phenomena