Ultra-high energy neutrino scattering

TL;DR

This paper estimates ultra-high energy neutrino cross sections by extrapolating proton structure functions using Froissart dependence, impacting neutrino detection experiments at energies above 10^9 GeV.

Contribution

It introduces a novel extrapolation method for neutrino cross sections based on Froissart dependence, differing from traditional perturbative QCD approaches.

Findings

Good agreement with perturbative QCD at lower energies

Cross sections are up to 10 times smaller above 10^9 GeV

Implications for ultra-high energy neutrino detection

Abstract

Estimates are made of the ultra-high energy neutrino cross sections based on an extrapolation to very small Bjorken x of the logarithmic Froissart dependence in x shown previously to provide an excellent fit to the measured proton structure function F_2^p(x,Q^2) over a broad range of the virtuality Q^2. Expressions are obtained for both the neutral current and the charged current cross sections. Comparison with an extrapolation based on perturbative QCD shows good agreement for energies where both fit data, but our rates are as much as a factor of 10 smaller for neutrino energies above 10^9 GeV, with important implications for experiments searching for extra-galactic neutrinos.