Intrinsic bottom and its impact on heavy new physics at the LHC

TL;DR

This paper investigates the non-perturbative intrinsic bottom quark distribution in the nucleon, demonstrating its evolution and impact on LHC processes, and introduces a model for intrinsic bottom PDFs.

Contribution

It shows that intrinsic heavy quark distributions evolve via non-singlet equations and provides a new model for intrinsic bottom PDFs relevant for LHC physics.

Findings

Intrinsic heavy quark evolution is governed by non-singlet equations.

Intrinsic bottom PDFs can significantly affect LHC parton luminosities.

The model estimates the non-perturbative contribution to heavy quark PDFs.

Abstract

Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting and do not involve any non-perturbative degrees of freedom. On the other hand, non- perturbative, intrinsic heavy quark parton distributions have been predicted in the literature. We demonstrate that to a very good approximation the scale-evolution of the intrinsic heavy quark content of the nucleon is governed by non-singlet evolution equations. This allows to analyze the intrinsic heavy quark distributions without having to resort to a full-fledged global analysis of parton distribution functions. We exploit this freedom to model intrinsic bottom distributions which are so far missing in the literature. We estimate the impact of the non-perturbative contribution to the charm and bottom-quark PDFs and on several important parton-parton luminosities at the LHC.