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DOE OSTI · 2349153

Parton distributions from boosted fields in the Coulomb gauge

Gao, Xiang·Liu, Wei-Yang·Zhao, Yong
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Abstract

We propose a new method to calculate parton distribution functions (PDFs) from lattice correlations of boosted quarks and gluons in the Coulomb gauge. Compared to the widely used gauge-invariant Wilson-line operators, these correlations greatly simplify the renormalization thanks to the absence of linear power divergence. Additionally, they enable access to larger off-axis momenta under preserved 3D rotational symmetry, as well as enhanced long-range precision that facilitates the Fourier transform. We verify the factorization formula that relates this new observable to the quark PDF at one-loop order in perturbation theory. Moreover, through a lattice calculation of the pion valence quark PDF, we demonstrate the aforementioned advantage and features of the Coulomb gauge correlation and show that it yields consistent results with the gauge-invariant method. This opens the door to a more efficient way to calculate parton physics on the lattice.

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BaryonsEffective field theoryGluonsHadronsLattice QCDLattice field theoryLattice gauge theoryMesonsParton distribution functionsPerturbative QCDQuantum electrodynamicsQuarks

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BibTeXRIS

Gao, Xiang, Liu, Wei-Yang, Zhao, Yong. 2024-05-10. Parton distributions from boosted fields in the Coulomb gauge. https://doi.org/10.1103/physrevd.109.094506

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