https://doi.org/10.1140/epjc/s10052-025-14142-9
Regular Article - Theoretical Physics
A method to include exclusive heavy vector-meson production data at small x in global parton analyses
1
Université Paris-Saclay, CNRS, IJCLab, 91405, Orsay, France
2
Institute for Particle Physics Phenomenology, Durham University, DH1 3LE, Durham, UK
3
Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, Gatchina, 188300, St. Petersburg, Russia
4
Department of Mathematical Sciences, University of Liverpool, L69 3BX, Liverpool, UK
a
christopher.flett@ijclab.in2p3.fr
Received:
29
November
2024
Accepted:
29
March
2025
Published online:
18
April
2025
We propose a method which allows the inclusion of exclusive heavy vector-meson production data at low x in future global parton analyses. As an example we perform a study within xFitter to determine the gluon parton distribution function (PDF) at next-to-leading order (NLO) at moderate-to-low x using the measurements of exclusive 
production in ep and pp collisions from HERA and LHC. We further study the constraints from the corresponding 
production process. We finish by discussing the possible effects at next-to-next-to-leading order (NNLO) through incorporation of a K factor for the exclusive heavy vector-meson coefficient function at NLO.
© The Author(s) 2025
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