Towards the three-dimensional parton structure of the pion: Integrating transverse momentum data into global QCD analysis

TL;DR

This paper advances the understanding of the pion's three-dimensional parton structure by integrating transverse momentum data into a comprehensive QCD analysis, combining multiple datasets to refine quark and gluon distribution models.

Contribution

It introduces a novel Monte Carlo QCD analysis that incorporates transverse momentum dependent data, enabling a more complete picture of the pion's internal structure.

Findings

Transverse momentum data significantly influence pion parton distribution functions.

The analysis reveals sensitivities to kinematic cuts and parametrization choices.

Results pave the way for combined collinear and TMD pion distribution studies.

Abstract

We perform a new Monte Carlo QCD analysis of pion parton distribution functions, including, for the first time, transverse momentum dependent pion-nucleus Drell-Yan cross sections together with $p_{\rm T}$-integrated Drell-Yan and leading neutron electroproduction data from HERA. We assess the sensitivity of the Monte Carlo fits to kinematic cuts, factorization scale, and parametrization choice, and we discuss the impact of the various datasets on the pion's quark and gluon distributions. This study provides the necessary step towards the simultaneous analysis of collinear and transverse momentum dependent pion distributions and the determination of the pion's three-dimensional structure.