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arXiv · 2507.22730

Pionic gluons from global QCD analysis of experimental and lattice data

William Good·Patrick C. Barry·Huey-Wen Lin·W. Melnitchouk·Alex NieMiera·Nobuo Sato
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Abstract

We perform the first global QCD analysis of parton distribution functions (PDFs) in the pion, with lattice-QCD data on gluonic pseudo--Ioffe-time distributions fitted simultaneously with experimental Drell-Yan and leading neutron electroproduction data. Inclusion of the lattice results with parametrized systematic corrections significantly reduces the uncertainties on the gluon PDF at parton momentum fractions $x \gtrsim 0.2$, revealing a higher gluon density in the pion at large $x$ than in the proton. The similar gluon momentum fractions in the pion and proton further suggests a relative suppression of the pion gluon density at small $x$.

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William Good, Patrick C. Barry, Huey-Wen Lin, W. Melnitchouk, Alex NieMiera, Nobuo Sato. 2025-07-30. Pionic gluons from global QCD analysis of experimental and lattice data. https://arxiv.org/abs/2507.22730

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