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arXiv · 2206.05672

The Proton Gluon Distribution from the Color Dipole Picture

G. R. Boroun·M. Kuroda·Dieter Schildknecht
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Abstract

Employing the representation of the experimental data on deep inelastic electron-proton scattering (DIS) in the color-dipole picture (CDP), we determine the gluon distribution of the proton at small Bjorken $x$. At sufficiently large momentum transfer, $Q^2$, the extracted gluon distribution fulfills the standard evolution equation for the proton structure function. For low values of $Q^2$, e.g. for $Q^2 = 1.9 {\rm GeV}^2$, the evolution equation for the proton structure function is violated. The standard procedure of adopting a low-$Q^2$ starting scale for the extraction of the gluon density is questionable and requires further investigations.

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G. R. Boroun, M. Kuroda, Dieter Schildknecht. 2022-06-12. The Proton Gluon Distribution from the Color Dipole Picture. https://doi.org/10.1140/epjp%2Fs13360-025-07059-5

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