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arXiv · 2111.04552

Overview of lattice calculations of the $x$-dependence of PDFs, GPDs and TMDs

Krzysztof Cichy
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Abstract

For a long time, lattice QCD was unable to address the $x$-dependence of partonic distributions, direct access to which is impossible in Euclidean spacetime. Recent years have brought a breakthrough for such calculations when it was realized that partonic light-cone correlations can be accessed through spatial correlations computable on the lattice. Appropriately devised observables can be factorized into physical PDFs via a perturbative procedure called matching, analogous to the standard factorization of experimental cross sections. In this short review, aimed at a broader high-energy and nuclear physics community, we discuss the recent highlights of this research program. Key concepts are outlined, followed by a case study illustrating the typical stage of current lattice extractions and by a brief review of the most recent explorations. We finalize with a number of messages for the prospects of lattice determinations of partonic structure.

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Krzysztof Cichy. 2021-11-08. Overview of lattice calculations of the $x$-dependence of PDFs, GPDs and TMDs. https://doi.org/10.1051/epjconf/202225801005

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