Impact of heavy-flavour production cross sections measured by the LHCb experiment on parton distribution functions at low x

TL;DR

This paper demonstrates how recent LHCb measurements of heavy-flavour production significantly improve the understanding of gluon and sea-quark distributions in the proton at very low x, a region previously lacking experimental constraints.

Contribution

It introduces a QCD analysis incorporating LHCb heavy-flavour data to refine parton distribution functions at low x, extending the kinematic reach of previous fits.

Findings

LHCb data constrains gluon and sea-quark PDFs at x ~ 5×10⁻⁶

Heavy-flavour measurements extend the low-x coverage in PDF fits

Improves the precision of proton structure understanding at very low x

Abstract

The impact of recent measurements of heavy-flavour production in deep inelastic $ep$ scattering and in $pp$ collisions on parton distribution functions is studied in a QCD analysis in the fixed-flavour number scheme at next-to-leading order. Differential cross sections of charm- and beauty-hadron production measured by LHCb are used together with inclusive and heavy-flavour production cross sections in deep inelastic scattering at HERA. The heavy-flavour data of the LHCb experiment impose additional constraints on the gluon and the sea-quark distributions at low partonic fractions $x$ of the proton momentum, down to $x \sim 5 \times 10^{-6}$. This kinematic range is currently not covered by other experimental data in perturbative QCD fits.