A new physics interpretation of the IceCube data

TL;DR

This paper proposes a new physics model involving ultrahigh energy neutrino interactions with small energy transfer, explaining IceCube's observed neutrino events better than standard models.

Contribution

It introduces a novel interpretation of IceCube data using TeV gravity or non-Wilsonian models that modify neutrino-nucleon cross sections.

Findings

Excellent fit to IceCube data with new physics model

Standard interactions cannot explain the observed angular and spectral features

Future data could distinguish this model from conventional astrophysical explanations

Abstract

IceCube has recently observed 37 events of TeV-PeV energies. The angular distribution, with a strong preference for downgoing directions, the spectrum, and the small muon to shower ratio in the data can not be accommodated assuming standard interactions of atmospheric neutrinos. We obtain an excellent fit, however, if a diffuse flux of ultrahigh energy (cosmogenic) neutrinos experiences collisions where only a small fraction of the energy is transferred to the target nucleon. We show that consistent models of TeV gravity or other non-Wilsonian completions of the standard model provide cross sections with these precise features. An increased statistics could clearly distinguish our scenario from the one assumed by IceCube (a diffuse flux of astrophysical neutrinos with a E^{-2} spectrum) and establish the need for new physics in the interpretation of the data.