The improved saturation model in nuclei

TL;DR

This paper develops an improved impact-parameter dependent dipole model to predict nuclear shadowing and saturation effects in deep-inelastic scattering at small x, relevant for future electron-ion collider experiments.

Contribution

It introduces an enhanced dipole model incorporating impact parameter dependence for nuclei, providing detailed predictions for nuclear shadowing and saturation phenomena.

Findings

Nuclear shadowing behavior is modeled across a wide impact parameter range.

Predicted nuclear saturation effects are observable at large dipole sizes.

Nuclear ratio behavior aligns with the GBW model across various nuclei.

Abstract

We consider the nuclear shadowing in deep-inelastic scattering corresponding to kinematic regions accessible by future experiments at electron-ion colliders. The gluon distribution at small $x$ is obtained using an improved dipole model depended on the impact parameter for atomic nucleus and compared with nCETQ15 parametrization group. The nuclear shadowing at small $x$ is defined within the color dipole formalism with respect to the mass number $A$. Its behavior is predicted for light nuclei in a wide range of the impact parameter $b$ and the transverse dipole size $r$. The nuclear saturation at large-$r$ (small $\mu^2$) is observable. The behavior of the nuclear ratio $\sigma^{A}_{\mathrm{dip}}/\sigma_{0}$ is similar to the Golec-Biernat-W$\ddot{\mathrm{u}}$sthoff (GBW) model in a wide range of $r$ for light and heavy nuclei at small $x$.