A model for pion collinear parton distribution function and form factor

TL;DR

This paper presents a new light-front wave function model for the pion that incorporates valence, sea, and gluon components, enabling accurate descriptions of its parton distribution functions and electromagnetic form factor.

Contribution

The paper introduces a novel pion light-front wave function model with separate parametrizations for longitudinal and transverse momentum dependencies, fitted to experimental data.

Findings

Pion PDFs are consistent with existing extractions.

The electromagnetic form factor fits all available data successfully.

The model effectively describes pion internal structure.

Abstract

We developed a model for the pion light-front wave function (LFWF) that incorporates valence, sea and gluon degrees of freedom. Using the LFWF overlap representation, we derived parametrizations for the pion parton distribution functions and the electromagnetic form factor. These parametrizations depend on two distinct sets of parameters, enabling separate fits of the longitudinal- and transverse-momentum dependencies of the LFWF. The pion PDFs are extracted from available Drell-Yan and photon-production data using the xFitter framework and are found well compatible with existing extractions. Furthermore, the fit of the electromagnetic form factor of the pion to all the available experimental data works quite successfully.