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arXiv · 2605.31424

CJ26 Global QCD Analysis with Large-$x$ Jefferson Lab 6 and 12 GeV Data

Abstract

We present CJ26, the new CTEQ-JLab global QCD analysis that incorporates for the first time the complete suite of JLab 6 GeV DIS measurements and the first published JLab 12 GeV measurements. Focused on the large-$x$ region, the analysis utilizes the increased $Q^2$ leverage of the 12 GeV data to uniquely disentangle higher-twist effects from off-shell nucleon corrections. This leads to a highly accurate determination of the $n/p$ structure function ratio and the $d/u$ valence quark ratio, with uncertainties reduced by 30-50% and 5-10%, respectively. We highlight the critical role of experimental correlated systematic uncertainties in achieving this precision and provide the resulting NLO PDFs and structure functions in LHAPDF format for general use.

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Alberto Accardi, Matteo Cerutti, Cynthia E. Keppel, Shujie Li, J. F. Owens, Sanghwa Park, Peter Risse. 2026-05-29. CJ26 Global QCD Analysis with Large-$x$ Jefferson Lab 6 and 12 GeV Data. https://arxiv.org/abs/2605.31424

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