CTEQ-TEA parton distribution functions with intrinsic charm

TL;DR

This paper investigates the potential nonperturbative intrinsic charm component in the proton's parton distribution functions, analyzing its theoretical interpretation, impact on LHC processes, and estimating its magnitude using global QCD fits with recent experimental data.

Contribution

It provides a comprehensive global analysis of intrinsic charm in PDFs, including new data and models, and discusses its implications for LHC phenomenology.

Findings

Nonperturbative charm can be significant in PDFs.

Different intrinsic charm models yield varying contributions.

Potential impact on LHC standard candle observables.

Abstract

The possibility of a (sizable) nonperturbative contribution to the charm parton distribution function (PDF) in a nucleon is investigated together with theoretical issues arising in its interpretation. Results from the global PDF analysis are presented. The separation of the universal component of the nonperturbative charm from the rest of the radiative contributions is discussed and the potential impact of a nonperturbative charm PDF on LHC scattering processes is illustrated. An estimate of nonperturbative charm magnitude in the CT14 and CT14HERA2 global QCD analyses at the next-to-next-to leading order (NNLO) in the QCD coupling strength is given by including the latest experimental data from HERA and the Large Hadron Collider (LHC). A comparison between different models of intrinsic charm is shown and prospects for standard candle observables at the LHC are illustrated.