Parton and nuclear dynamics at large x: the CJ26 global QCD analysis
Abstract
We present the new CTEQ-JLab global QCD analysis, called CJ26, that simultaneously fits parton distribution functions of the proton and nuclear effects in deuteron targets. This work includes, for the first time in a global fit, the full set of JLab 6 GeV inclusive DIS measurements and the first published JLab 12 GeV data. The analysis focuses on the large-x region, and carefully treats the interplay between higher-twist effects and off-shell corrections in low-energy proton and deuteron target data. We discuss their effect on quark and gluon distributions, and highlight the importance of quantifying the experimental correlated systematic uncertainty to achieve fits of the highest accuracy. We also outline how upcoming data may help unravel the nuclear and partonic dynamics in light nuclei. The extracted next-to-leading order parton distributions are available on the CJ web pages in LHAPDF format for general use, accompanied by leading- and higher-twist structure functions calculated with the simultaneously fitted PDFs, higher-twist corrections, and off-shell corrections. This write up clarifies several points that became clearer while finalizing the CJ26 paper and can be read as a companion to the latter.
Related
- Global Analysis of Nuclear Parton Distribution Functions using Markov Chain Monte Carlo
- Unified description of longitudinal and transverse parton dynamics in cold nuclear matter
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- nCTEQ26 nuclear parton distribution functions
BibTeX
@misc{accardi2026parton,
title = {{Parton and nuclear dynamics at large $x$: the CJ26 global QCD analysis}},
author = {Alberto Accardi and Matteo Cerutti and Cynthia E. Keppel and Shujie Li and J. F. Owens and Sanghwa Park and Peter Risse},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.17485},
eprint = {2610.17485},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.17485},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Parton and nuclear dynamics at large x: the CJ26 global QCD analysis
AU - Alberto Accardi
AU - Matteo Cerutti
AU - Cynthia E. Keppel
AU - Shujie Li
AU - J. F. Owens
AU - Sanghwa Park
AU - Peter Risse
PY - 2026
DA - 2026/10/12
PB - arXiv
DO - 10.48550/arxiv.2610.17485
UR - https://arxiv.org/abs/2610.17485
AB - We present the new CTEQ-JLab global QCD analysis, called CJ26, that simultaneously fits parton distribution functions of the proton and nuclear effects in deuteron targets. This work includes, for the first time in a global fit, the full set of JLab 6 GeV inclusive DIS measurements and the first published JLab 12 GeV data. The analysis focuses on the large-x region, and carefully treats the interplay between higher-twist effects and off-shell corrections in low-energy proton and deuteron target data. We discuss their effect on quark and gluon distributions, and highlight the importance of quantifying the experimental correlated systematic uncertainty to achieve fits of the highest accuracy. We also outline how upcoming data may help unravel the nuclear and partonic dynamics in light nuclei. The extracted next-to-leading order parton distributions are available on the CJ web pages in LHAPDF format for general use, accompanied by leading- and higher-twist structure functions calculated with the simultaneously fitted PDFs, higher-twist corrections, and off-shell corrections. This write up clarifies several points that became clearer while finalizing the CJ26 paper and can be read as a companion to the latter.
ER -