Parton distribution functions probed in ultraperipheral collisions at the CERN Large Hadron Collider

Abstract

Vector meson production in ultra-peripheral pA and AA collisions at the CERN Large Hadron Collider (LHC) are very sensitive to Parton Distribution Functions (PDF) as well as to their leading-order, next-to-leading-order, and medium corrections. This process is a complimentary tool to explore the effects of different PDFs in particle production in proton-nucleus and nucleus-nucleus central collisions. Existing and forthcoming data available, e.g., from ALICE and CMS, may be used in conjunction with our theoretical predictions to constrain the PDFs. We make predictions for rapidity distributions and for cross sections of J/$\psi$ , $\psi(2S)$ and $\Upsilon$ production at $\sqrt{s_{NN}}=2.76$ TeV and $\sqrt{s_{NN}}=5$ TeV. We use the second energy as representative for the Run 2 of PbPb collisions at the LHC.