Constraints on atmospheric charmed-meson production from IceCube

TL;DR

This paper discusses the challenges in calculating charm quark production at ultra-high energies relevant for IceCube, and presents the strongest limits on prompt neutrino flux based on IceCube data.

Contribution

It provides new constraints on atmospheric charm production and prompt neutrino flux using IceCube observations, addressing uncertainties in charm cross-section calculations.

Findings

Established the strongest limit on prompt neutrino flux from IceCube data.

Highlighted the uncertainties in charm production cross-section at high energies.

Discussed the perturbative calculation of charm quark production and non-perturbative contributions.

Abstract

At very-high energies (100 TeV - 1 PeV), the small value of Bjorken-x ($\le10^{-3}-10^{-7}$) at which the parton distribution functions are evaluated makes the calculation of charm quark production very difficult. The charm quark has mass ($\sim$1.5$\pm$0.2 GeV) significantly above the $\Lambda$$_{QCD}$ scale ($\sim$200 MeV), and therefore its production is perturbatively calculable. However, the uncertainty in the data and the calculations cannot exclude some smaller non-perturbative contribution. To evaluate the prompt neutrino flux, one needs to know the charm production cross-section in pN -> c$\bar{c}$ X, and hadronization of charm particles. This contribution briefly discusses computation of prompt neutrino flux and presents the strongest limit on prompt neutrino flux from IceCube.