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arXiv · 2510.26425

Unpolarized gluon PDF of the nucleon from lattice QCD at physical point in the continuum limit

Chen Chen·Chunhua Zeng·Hongxin Dong·Liuming Liu·Xiaomin Shen·Peng Sun·Xiaonu Xiong·Yi-Bo Yang·Fei Yao·Jian-Hui Zhang·Shiyi Zhong
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Abstract

We report a state-of-the-art lattice QCD calculation of the nucleon unpolarized gluon parton distribution function employing large-momentum effective theory. The calculation is carried out on the 2+1 flavor CLQCD ensembles with five lattice spacings a={0.105,0.0897,0.0775, 0.0688, 0.0519} fm and various pion masses ranging from 136 MeV to 317 MeV, covering nulceon momenta up to 3 GeV. Distillation technique is applied to improve the signal of two-point correlators. We then apply the state-of-the-art hybrid renormalization and one-loop perturbative matching, and extrapolate the result to the continuum limit, infinite momentum limit and physical pion mass.

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Chen Chen, Chunhua Zeng, Hongxin Dong, Liuming Liu, Xiaomin Shen, Peng Sun, Xiaonu Xiong, Yi-Bo Yang, Fei Yao, Jian-Hui Zhang, Shiyi Zhong. 2025-10-30. Unpolarized gluon PDF of the nucleon from lattice QCD at physical point in the continuum limit. https://arxiv.org/abs/2510.26425

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