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arXiv · 2505.22795

Window observables for benchmarking parton distribution functions

Joe Karpie·Christopher J. Monahan·Kostas Orginos·Savvas Zafeiropoulos
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Abstract

Global analysis of collider and fixed-target experimental data and calculations from lattice quantum chromodynamics (QCD) are used to gain complementary information on the structure of hadrons. We propose novel ``window observables'' that allow for higher precision cross-validation between the different approaches, a critical step for studies that wish to combine the datasets. Global analyses are limited by the kinematic regions accessible to experiment, particularly in a range of Bjorken-$x$, and lattice QCD calculations also have limitations requiring extrapolations to obtain the parton distributions. We provide two different ``window observables'' that can be defined within a region of $x$ where extrapolations and interpolations in global analyses remain reliable and where lattice QCD results retain sensitivity and precision.

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Joe Karpie, Christopher J. Monahan, Kostas Orginos, Savvas Zafeiropoulos. 2025-05-28. Window observables for benchmarking parton distribution functions. https://doi.org/10.1103/q6jl-816j

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