Measurement of J/ψ production cross-sections in pp collisions at √s=5 TeV

作者：Aaij, R.; Abdelmotteleb, A. S. W.; Beteta, C. Abellan; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Agapopoulou, C.; Aidala, C. A.; Aiola, S.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Alfonso Albero, A.; Aliouche, Z.; Alkhazov, G.; Cartelle, P. Alvarez; Amato, S.; Amey, J. L.; Amhis, Y.; An, L.; Anderlini, L.; Andreianov, A.; Andreotti, M.; Archilli, F.; Artamonov, A.; Artuso, M.; Arzymatov, K.; Aslanides, E.; Atzeni, M.; Audurier, B.; Bachmann, S.

来源：JOURNAL OF HIGH ENERGY PHYSICS, 2021, (11): 181.

DOI：10.1007/JHEP11(2021)181

• Hadron-Hadron scattering (experiments)
• Heavy quark production
• QCD
• Quarkonium

The production cross-sections of J/psi mesons in proton-proton collisions at a centre-of-mass energy of root s = 5TeV are measured using a data sample corresponding to an integrated luminosity of 9.13 +/- 0.18 pb(-1), collected by the LHCb experiment. The cross-sections are measured differentially as a function of transverse momentum, p(T), and rapidity, y, and separately for J/psi mesons produced promptly and from beauty hadron decays (nonprompt). With the assumption of unpolarised J/psi mesons, the production cross-sections integrated over the kinematic range 0 < p(T) < 20 GeV/c and 2.0 < y < 4.5 are @@@ sigma(prompt) J/psi = 8.154 +/- 0.010 +/- 0.283 mu b, @@@ sigma(nonprompt) J/psi = 0.820 +/- 0.003 +/- 0.034 mu b, @@@ where the first uncertainties are statistical and the second systematic. These cross-sections are compared with those at root s = 8TeV and 13TeV, and are used to update the measurement of the nuclear modification factor in proton-lead collisions for J/psi mesons at a centre-of-mass energy per nucleon pair of root s(NN) = 5TeV. The results are compared with theoretical predictions.