Comparison of $\psi(2S)$ and $J/\psi$ photoproduction cross sections in Pb-Pb ultraperipheral collisions at the LHC

TL;DR

This paper compares the photoproduction cross sections of $J/psi$ and $psi(2S)$ mesons in lead-lead ultraperipheral collisions at the LHC, highlighting the similar nuclear suppression effects due to gluon shadowing.

Contribution

It provides a theoretical comparison of $J/psi$ and $psi(2S)$ production cross sections using perturbative QCD and nuclear shadowing models.

Findings

Nuclear suppression of both mesons is large.

Suppression effects are similar for $J/psi$ and $psi(2S)$.

Gluon shadowing significantly impacts cross sections.

Abstract

Within the leading logarithmic approximation of perturbative QCD and the leading twist approach to nuclear shadowing, we compare the cross sections of photoproduction of $J/\psi$ and $\psi(2S)$ mesons on nuclei in Pb-Pb UPCs in the LHC kinematics. We find that the nuclear suppression of these cross sections due to the nuclear gluon shadowing is large and rather similar in the $J/\psi$ and $\psi(2S)$ cases.