Nuclear effects in photoproduction of heavy quarks and vector mesons in ultraperipheral PbPb and $p$Pb collisions at energies available at the CERN Large Hadron Collider

Nuclear effects in photoproduction of heavy quarks and vector mesons in ultraperipheral PbPb and $p$ Pb collisions at energies available at the CERN Large Hadron Collider

Adeola Adeluyi, C. A. Bertulani, and M. J. Murray

Phys. Rev. C 86, 047901 – Published 22 October 2012

Abstract

The comparison of photoproduction cross sections for $c \bar{c}$ and $b \bar{b}$ in PbPb and $p$ Pb collisions can show sensitivity to nuclear shadowing effects. The photoproduction of vector mesons is even more sensitive to the underlying gluon distributions. In this study we present the cross sections and rapidity dependence of the photoproduction of heavy quarks and the exclusive production of vector mesons in ultraperipheral $p$ Pb and PbPb collisions at the CERN Large Hadron Collider at $\sqrt{s_{_{N N}}} = 5$ TeV and $\sqrt{s_{_{N N}}} = 2.76$ TeV, respectively. The potentials of using these processes for constraining nuclear gluon shadowing are explored. It is found that the photoproduction of $J / ψ$ and $Υ$ in PbPb collisions in particular exhibits very good sensitivity to gluon shadowing.