Window observables for benchmarking parton distribution functions

TL;DR

This paper introduces novel window observables that enable precise cross-validation of parton distribution functions derived from collider data and lattice QCD, improving the reliability of hadron structure studies.

Contribution

It proposes two new window observables that facilitate higher precision comparison between experimental global analyses and lattice QCD calculations within reliable kinematic regions.

Findings

Two window observables defined within reliable x regions

Enhanced cross-validation between experimental and lattice results

Potential for improved global analysis accuracy

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.