Coherent photoproduction of $\psi$ and ${\rm Y}$ 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 $J/\psi (1s)$, $\psi (2s)$, ${\rm Y}(1s)$, ${\rm Y}(2s)$, and ${\rm Y}(3s)$ 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.

Comments: 4 pages, 4 figures, added and updated references, accepted for publication in Physical Review C