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arXiv · 2406.12936

Global fits of proton PDFs with non-linear corrections from gluon recombination

Pit Duwentäster·Vadim Guzey·Ilkka Helenius·Hannu Paukkunen
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Abstract

We present numerical studies of the leading non-linear corrections to the DGLAP evolution equations of parton distribution functions (PDFs) resulting from gluon recombination, which reduce the pace of evolution at small momentum fractions $x$. The non-linear evolution is implemented in the \textsc{HOPPET} and \textsc{xFitter} toolkits and used to carry out fits of proton PDFs using lepton-proton deep inelastic scattering data from HERA, BCDMS and NMC. While we do not find evidence for non-linear effects, we are able to set upper limits for their strength. We also quantify the potential impact of longitudinal structure function measurements at the Electron-Ion Collider and the Large Hadron Electron Collider on future fits.

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Pit Duwentäster, Vadim Guzey, Ilkka Helenius, Hannu Paukkunen. 2024-06-17. Global fits of proton PDFs with non-linear corrections from gluon recombination. https://arxiv.org/abs/2406.12936

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