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The measurement of the nuclear structure function $F_2^A (x,Q^2)$ at the future electron-ion collider (EIC) will be of great relevance to understand the origin of the nuclear shadowing and to probe gluon saturation effects. Currently there are several phenomenological models, based on very distinct approaches, which describe the scarce experimental data quite successfully. One of main uncertainties comes from the schemes used to include the effects associated to the multiple scatterings and to unitarize the cross section. In this paper we compare the predictions of three different unitarization schemes of the nuclear structure function which use the same theoretical input to describe the projectile-nucleon interaction. In particular, we consider as input the predictions of the Color Glass Condensate formalism, which reproduce the inclusive and diffractive $ep$ HERA data. Our results suggest that the experimental analysis of $F_2^A$ will be able to discriminate between the unitarization schemes.

Within the framework of a (1+1)--dimensional model which mimics high energy QCD, we study the behavior of the cross sections for inclusive and diffractive deep inelastic $\gamma^*h$ scattering cross sections. We analyze the cases of both fixed and running coupling within the mean field approximation, in which the evolution of the scattering amplitude is described by the Balitsky-Kovchegov equation, and also through the pomeron loop equations, which include in the evolution the gluon number fluctuations. In the diffractive case, similarly to the inclusive one, the suppression of the diffusive scaling, as a consequence of the inclusion of the running of the coupling, is observed.

We show how the AGBS model, originally developed for deep inelastic scattering applied to HERA data on the proton structure function, can also describe the RHIC data on single inclusive hadron yield for $d+Au$ and $p+p$ collisions through a new simultaneous fit. The single inclusive hadron production is modeled through the color glass condensate, which uses the quark(and gluon)--condensate amplitudes in momentum space. The AGBS model is also a momentum space model based on the asymptotic solutions of the BK equation, although a different definition of the Fourier transform is used. This aspect is overcome and a description entirely in transverse momentum of both processes arises for the first time. The small difference between the simultaneous fit and the one for HERA data alone suggests that the AGBS model describes very well both kind of processes and thus emerges as a good tool to investigate the inclusive hadron production data. We use this model for predictions at LHC energies, which agree very well with available experimental data., 10 pages, 7 figures

We show that ${\ensuremath{\Sigma}}^{+}$ hyperons produced by 800 GeV/c protons on targets of Be and Cu have significant polarizations (15--20%). These polarizations persist at values of ${p}_{t}\ensuremath{\approx}2\text{ }\text{ }\mathrm{G}\mathrm{e}\mathrm{V}/\mathrm{c}$ and a wide range of ${x}_{F}$. The polarizations from the Cu target are consistently less than from Be. The average ratio of the ${\ensuremath{\Sigma}}^{+}$ polarization from Cu to that from Be is $0.68\ifmmode\pm\else\textpm\fi{}0.08$.