Recent ALICE results relevant for PDFs at low and high-$x$, saturation

TL;DR

This paper reports on ALICE's recent measurements of J/ψ photoproduction in ultra-peripheral collisions, offering insights into gluon saturation and shadowing effects at low and high Bjorken-x, with implications for parton distribution functions.

Contribution

It provides new experimental data on coherent and incoherent J/ψ production in ultra-peripheral collisions, enhancing understanding of the initial state of protons and ions.

Findings

Evidence for gluon saturation effects at low-x

Constraints on nuclear shadowing models

Potential for improved PDFs with future data

Abstract

We present recent results from the ALICE Collaboration on the study of coherent and incoherent J/$\psi$ photoproduction in ultra-peripheral Pb-Pb collisions, including results from exclusive and dissociate J/$\psi$ mesons in ultra-peripheral p-Pb interactions. These measurements provide unique insights into the initial state of protons and ions, with great sensitivity for both gluon saturation and shadowing. Furthermore, we will discuss the prospects for these measurements using the Run 3 and Run 4 data.