Constraints on the origins of the ultra-high energy cosmic-rays using the IceCube diffuse neu-trino limits : An analytical approach

摘要

Astrophysical neutrinos are expected to be produced in the interactions of the ultra-high energy cosmic-rayprotons with surrounding photons. Therefore astrophysical neutrino model fluxes are highly dependent on characteristicsof the cosmic-ray sources, such as their cosmological distributions and the photon field in each sources. We study possibleconstraints on the properties of cosmic-ray sources in a model-independent way using the recently obtained upperlimiton the diffuse flux of neutrinos with energies above 100 PeV by the IceCube detector. The semi-analytic formula isderived to estimate the fluxes of cosmogenic neutrinos as functions of source evolution parameter and source extensionin redshift. Then the obtained formula enables us to convert the upperlimits on the neutrino fluxes into the constraints onthe cosmic-ray sources. It is found that the recently obtained upperlimit on the cosmogenic neutrinos by IceCube tightlyconstrains the very high source evolution scenarios. The derived analytic formula also shows that the future limits fromthe 1km 3 scale detectors such as IceCube and KM3NET are able to further constrain the the ultra-high energy cosmic-rayssources with evolutions comparable to the cosmic star formation rate.