Origin of the high energy neutrino flux at IceCube

Abstract

We discuss the spectrum of the different components in the astrophysical neutrino flux reaching the Earth and the possible contribution of each component to the high-energy IceCube data. We show that the diffuse flux from cosmic ray interactions with gas in our galaxy implies just 2 events among the 54 event sample. We argue that the neutrino flux from cosmic ray interactions in the intergalactic (intracluster) space depends critically on the transport parameter $\delta$ describing the energy dependence in the diffusion coefficient of galactic cosmic rays. Our analysis motivates a E^{-2.1} neutrino spectrum with a drop at PeV energies that fits well the data, including the non-observation of the Glashow resonance at 6.3 PeV. We also show that a cosmic ray flux described by an unbroken power law may produce a neutrino flux with interesting spectral features (bumps and breaks) related to changes in the cosmic ray composition.

19 pages, new section about changes in CR composition, version to appear in ApJ

References in corpus (12)

• The Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived From First-Year Fermi Large Area Telescope Data
• Cosmic-Ray Proton and Helium Spectra from the First CREAM Flight
• Atmospheric and Astrophysical Neutrinos above 1 TeV Interacting in IceCube
• Spectral breaks as a signature of cosmic ray induced turbulence in the Galaxy
• High-energy gamma-ray and neutrino backgrounds from clusters of galaxies and radio constraints
• Galaxy Clusters as Reservoirs of Heavy Dark Matter and High-Energy Cosmic Rays: Constraints from Neutrino Observations
• On the Charm Contribution to the Atmospheric Neutrino Flux
• On the IceCube spectral anomaly
• Chemical Composition of Galactic Cosmic Rays with Space Experiments
• A new physics interpretation of the IceCube data
• The shape of the extragalactic cosmic ray spectrum from Galaxy Clusters
• Diffuse flux of galactic neutrinos and gamma rays

Cited by in corpus (2)

• Lorentz violation footprints in the spectrum of high-energy cosmic neutrinos: Deformation of the spectrum of superluminal neutrinos from electron-positron pair production in vacuum
• Neutrino events within muon bundles at neutrino telescopes