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arXiv · 2606.16877

Direct calculation of parton distributions in momentum space from lattice QCD

Anthony V. Grebe·Daniel C. Hackett·Michael L. Wagman·Rui Zhang·Yong Zhao
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Abstract

Coulomb-gauge quasi-parton distributions can be computed directly in momentum space on a finite lattice, enabled by the commutativity of their renormalization and Fourier transform. This approach removes the formal inverse problem in coordinate-space methods. Our momentum-space pion quasi-distributions agree with coordinate-space results Fourier transformed with asymptotic extrapolation, indicating that the formal inverse problem in the latter is not a concern at this volume. We further extend the framework to higher dimensions and obtain the first 3D image of the pion directly from lattice QCD.

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Anthony V. Grebe, Daniel C. Hackett, Michael L. Wagman, Rui Zhang, Yong Zhao. 2026-06-15. Direct calculation of parton distributions in momentum space from lattice QCD. https://arxiv.org/abs/2606.16877

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