Inclusive quarkonium production in pp collisions at √s=5.02 TeV

This article reports on the inclusive production cross section of several quarkonium states, J/psi, psi(2S), Upsilon(1S), Upsilon(2S), and Upsilon(3S), measured with the ALICE detector at the LHC, in pp collisions at root s = 5.02 TeV. The analysis is performed in the dimuon decay channel at forward rapidity (2.5 < y < 4). The integrated cross sections and transverse-momentum (p(T)) and rapidity (y) differential cross sections for J/psi, psi(2S), Upsilon(1S), and the psi(2S)-to-J/psi cross section ratios are presented. The integrated cross sections, assuming unpolarized quarkonia, are: sigma(J/psi) (p(T) < 20 GeV/c) = 5.88 +/- 0.03 +/- 0.34 mu b, sigma(psi(2S)) (p(T) < 12 GeV/c) = 0.87 +/- 0.06 +/- 0.10 mu b, sigma(Upsilon(1S)) (p(T) < 15 GeV/c) = 45.5 +/- 3.9 +/- 3.5 nb, sigma(Upsilon(2S)) (p(T) < 15 GeV/c) = 22.4 +/- 3.2 +/- 2.7 nb, and sigma(Upsilon(3S)) (p(T) < 15 GeV/c) = 4.9 +/- 2.2 +/- 1.0 nb, where the first (second) uncertainty is the statistical (systematic) one. For the first time, the cross sections of the three Upsilon states, as well as the psi(2S) one as a function of p(T) and y, are measured at root s = 5.02 TeV at forward rapidity. These measurements also significantly extend the J/psi p(T) reach and supersede previously published results. A comparison with ALICE measurements in pp collisions at root s = 2.76, 7, 8, and 13 TeV is presented and the energy dependence of quarkonium production cross sections is discussed. Finally, the results are compared with the predictions from several production models.

Automated summary

This article reports on the inclusive production cross section of several quarkonium states, J/psi, psi(2S), Upsilon(1S), Upsilon(2S), and Upsilon(3S), measured with the ALICE detector at the LHC, in pp collisions at root s = 5.02 TeV. The measurements also significantly extend the J/psi p(T) reach and supersede previously published results。