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arXiv · 2207.03378

Small-x Evolution of the Gluon Generalized Parton Distribution Eg of the Nucleon

Yoshitaka Hatta·Jian Zhou
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Abstract

We study the small-$x$ evolution equation for the gluon generalized parton distribution (GPD) $E_g$ of the nucleon. It is shown that $E_g$ at vanishing skewness exhibits the Regge behavior identical to the BFKL Pomeron, despite its association with nucleon helicity-flip processes. We also consider the effect of gluon saturation and demonstrate that $E_g$ gets saturated in the same way as its helicity-nonflip counterpart $H_g$. Our result has a direct impact on the modeling of $E_g$ as well as the small-$x$ contribution to nucleon spin sum rules.

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Yoshitaka Hatta, Jian Zhou. 2022-12-21. Small-x Evolution of the Gluon Generalized Parton Distribution Eg of the Nucleon. https://doi.org/10.1103/physrevlett.129.252002

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