Search arXivSearch

arXiv · 2510.26425

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

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.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chen Chen, Chunhua Zeng, Hongxin Dong, Liuming Liu, Xiaomin Shen, Peng Sun, Xiaonu Xiong, Yi-Bo Yang, Fei Yao, Jian-Hui Zhang, Shiyi Zhong. 2026-07-30. Unpolarized gluon PDF of the nucleon from lattice QCD at physical point in the continuum limit. https://arxiv.org/abs/2510.26425

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

When the center matters: color screening and gluelumps in dihedral lattice gauge theories

Confinement is one of the hallmarks of quantum chromodynamics (QCD), but its first-principles characterization remains elusive. We show that discrete non-Abelian lattice gauge theories (LGTs) with dihedral groups $D_N$ provide a minimal setup for characterizing the connection between confinement and the group center. When the latter is trivial (odd $N$), gluon clouds screen static charges, forming composite objects known as gluelumps. These are stable excitations of the theory, in contrast to their QCD analog. As a consequence, string breaking can occur through fluctuations of the electric field only, without pair nucleation from the vacuum. Our results showcase how the rich physics typically associated with QCD emerges in much simpler discrete non-Abelian LGTs, making them ideal settings to test this phenomenology both in numerical calculations and in near-term quantum devices.

hep-lat

Confining Flux Tube in the Trace Deformed (2+1) Dimensional SU(2) Gauge Theory

We study the confining flux tube in the reconfined phase of trace deformed SU(2) Yang-Mills theory in (2+1) dimensions. Using lattice simulations above the standard deconfinement temperature, we analyze Polyakov-loop correlators and extract the ground state energy of the effective string. We show that the usual Nambu-Goto effective string description, including its standard higher-order corrections, fails to reproduce the data as the trace deformation is increased. Remarkably, deep in the reconfined regime the results are instead accurately described by the Polchinski-Yang rigid-string solution, corresponding to an effective string dominated by an extrinsic-curvature term. We further investigate the transverse profile of the chromo-electric flux tube and find significant deviations from the standard Yang-Mills behavior, including a substantial modification of the intrinsic width. Finally, we present an exploratory study of the phase diagram, finding evidence for a transition from a continuous to a first order reconfinement line as the deformation parameter increases. These results suggest that the reconfined phase realizes a qualitatively different effective-string regime from ordinary confinement.

hep-lat

Quantum anomaly for benchmarking quantum computing

Given the rapid advances in quantum computing hardware, establishing strategies for verifying the correctness of quantum computations has become increasingly important. Exploiting the fact that the axial anomaly in gauge theories is exact to all orders in perturbation theory, we propose the axial anomaly as a nontrivial benchmark for quantum simulations of lattice gauge theories. We simulate axial charge production in ${\mathbb Z}_N$ lattice gauge theories on the trapped-ion quantum computer ``Reimei''. After taking the U(1), infinitesimal time, and infinite volume limits, we successfully reproduce the anomaly coefficient within statistical uncertainties, even without error mitigation. Our results demonstrate that the axial anomaly can be simulated on current quantum computers and serves as a verification test of quantum computations.

hep-lat