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  • Letter
  • Open Access

Gluonic contributions to the pion parton distribution functions

Jiangshan Lan1,2,3,4,*, Chandan Mondal1,2,3,†, Xingbo Zhao1,2,3,4,‡, Tobias Frederico5,§, and James P. Vary6,∥

  • *Contact author: jiangshanlan@impcas.ac.cn
  • †Contact author: mondal@impcas.ac.cn
  • ‡Contact author: xbzhao@impcas.ac.cn
  • §Contact author: tobias@ita.br
  • ∥Contact author: jvary@iastate.edu
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Phys. Rev. D 111, L111903 – Published 16 June, 2025

DOI: https://doi.org/10.1103/3z39-l1kg

Abstract

We investigate gluonic contributions to the pion beyond the valence sector using basis light-front quantization (BLFQ) and the Minkowski Bethe-Salpeter equation (BSE). Starting from the valence light-front wave function, we construct the quark-antiquark-gluon component and derive the corresponding quark and gluon parton distribution functions (PDFs). A proposed operator generating this higher Fock sector is validated against BLFQ and BSE results. We identify dynamical chiral symmetry breaking through enhanced spin-flip transitions, which amplify the low-x quark PDF and underlie the π−ρ mass splitting. The framework also reveals the impact of a vanishing gluon mass on the gluon PDF, highlighting sensitivity to nonperturbative gluon dynamics.

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Outline

Information

Phys. Rev. D 111, L111903– Published 16 June, 2025
  • Received 13 January 2025
  • Accepted 6 May 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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