Lepton fluxes from atmospheric charm revisited

TL;DR

This paper updates predictions for atmospheric lepton fluxes from charm quark production using advanced QCD calculations, highlighting larger uncertainties that impact neutrino observatory data interpretation.

Contribution

It provides the most recent and comprehensive charm hadroproduction calculations, incorporating higher-order QCD results and uncertainty estimates, improving flux predictions for neutrino experiments.

Findings

Predictions are compatible with recent literature within uncertainties.

Total uncertainties are significantly larger when including previously neglected contributions.

Results are essential for interpreting neutrino signals in IceCube.

Abstract

We update predictions for lepton fluxes from the hadroproduction of charm quarks in the scattering of primary cosmic rays with the Earth's atmosphere. The calculation of charm-pair hadroproduction applies the latest results from perturbative QCD through next-to-next-to-leading order and modern parton distributions, together with estimates on various sources of uncertainties. Our predictions for the lepton fluxes turn out to be compatible, within the uncertainty band, with recent results in the literature. However, by taking into account contributions neglected in previous works, our total uncertainties are much larger. The predictions are crucial for the interpretation of results from neutrino experiments like IceCube, when disentangling signals of neutrinos of astrophysical origin from the atmospheric background.