Calculation of High Energy Neutrino-Nucleon Cross Sections and Uncertainties Using the MSTW Parton Distribution Functions and Implications for Future Experiments

TL;DR

This paper calculates high-energy neutrino-nucleon cross sections using MSTW PDFs, quantifies uncertainties, and discusses implications for future experiments to detect potential deviations indicating new physics.

Contribution

It provides updated cross section calculations, uncertainty estimates, and parametrizations for ultra-high energy neutrino interactions based on the latest MSTW PDFs.

Findings

Cross sections are computed for energies from 10^4 to 10^12 GeV.

Uncertainty bounds are propagated from the MSTW PDFs.

Future experiments could constrain new physics through deviations in measured cross sections.

Abstract

We present a new calculation of the cross sections for charged current (CC) and neutral current (NC) $\nu N$ and $\bar{\nu} N$ interactions in the neutrino energy range $10^{4}<E_{\nu}<10^{12}$ GeV using the most recent MSTW parton distribution functions (PDFs), MSTW 2008. We also present the associated uncertainties propagated from the PDFs, as well as parametrizations of the cross section central values, their uncertainty bounds, and the inelasticity distributions for ease of use in Monte Carlo simulations. For the latter we only provide parametrizations for energies above $10^7$ GeV. Finally, we assess the feasibility of future neutrino experiments to constrain the $\nu N$ cross section in the ultra-high energy (UHE) regime using a technique that is independent of the flux spectrum of incident neutrinos. A significant deviation from the predicted Standard Model cross sections could be an indication of new physics, such as extra space-time dimensions, and we present expected constraints on such models as a function of the number of events observed in a future subterranean neutrino detector.