Coherent photoproduction of $\psi$ and $\Upsilon$ mesons in ultraperipheral pPb and PbPb collisions at the CERN LHC

Abstract

Exclusive photoproduction of vector mesons in the perturbative two-gluon exchange formalism depends significantly on nucleon and nuclear gluon distributions. In the present study we calculate total cross sections and rapidity distributions of $J/\psi(1s)$, $\psi(2s)$, $\Upsilon(1s)$, $\Upsilon(2s)$, and $\Upsilon(3s)$ in ultraperipheral proton-lead (pPb) and lead-lead (PbPb) collisions at the CERN Large Hadron Collider (LHC) at $\sqrt{s_{_{NN}}}=5$ TeV and $\sqrt{s_{_{NN}}}=2.76$ TeV respectively. Effects of gluon shadowing are investigated and potentials for constraining nuclear gluon modifications are discussed.