Inclusive J/ψ production at midrapidity in pp collisions at √s = 13 TeV

Abstract

We report on the inclusive J/ψ production cross section measured at the CERN Large Hadron Col- lider in proton–proton collisions at a center-of-mass energy √s = 13 TeV. The J/ψ mesons are reconstructed in the e+e− decay channel and the measurements are performed at midrapidity (|y| < 0.9) in the transverse-momentum inter- val 0 < pT < 40 GeV/c, using a minimum-bias data sample corresponding to an integrated luminosity Lint = 32.2 nb−1 and an Electromagnetic Calorimeter triggered data sample with L int = 8.3 pb−1 . The pT -integrated J/ψ production cross section at midrapidity, computed using the minimum- bias data sample, is dσ/dy|y=0 = 8.97 ± 0.24 (stat) ± 0.48 (syst) ± 0.15 (lumi) μb. An approximate logarith- mic dependence with the collision energy is suggested by these results and available world data, in agreement with model predictions. The integrated and pT-differential mea- surements are compared with measurements in pp collisions at lower energies and with several recent phenomenologi- cal calculations based on the non-relativistic QCD and Color Evaporation models.