2016/01/01 by Anna Cisek, Antoni Szczurek · 2 citations
Physics and Astronomy · #Gluon #High-Energy Particle Collisions Research #Large Hadron Collider #Meson #Particle physics theoretical and experimental studies #Production (economics) #Quantum Chromodynamics and Particle Interactions #Rapidity #Saturation (graph theory) #hep-ph
paper · pdf · doi:10.1051/epjconf/201613005003
published in EPJ Web of Conferences 130, 05003 (EDP Sciences) · 4 pages, 4 figures, a talk by A. Cisek at MESON2016 workshop, Krakow, June 2-7, 2016
openalex publication_date 2016/01/01 · arxiv created 2016/09/27 · arxiv updated 2016/12/21 · openalex created_date 2017/06/30 · openalex updated_date 2026/08/05
We discuss the prompt production of J/ψ mesons in proton-proton collisions at the LHC within a NRQCD kt-factorization approach using Kimber-Martin-Ryskin (KMR) unintegrated gluon distributions (UGDF). We include both direct color-singlet production (gg → J/ψg) as well as a feed-down from χc → J/ψγ and ψ′ → J/ψX. The production of the decaying mesons (χc or ψ′) is also calculated within NRQCD ktfactorization. The corresponding matrix elements for gg → J/ψ, gg → ψ′ and gg → χc include parameters of the nonrelativistic spatial wave functions of quarkonia at r = 0, which are taken from potential models from the literature. We get the ratio of the corresponding of the cross sections for χc(2)-to-χc(1) much closer to experimental data than obtained in recent analyses. Differential distributions in rapidity of J/ψ and ψ′ are calculated and compared to experimental data of the ALICE and LHCb collaborations. We discuss possible onset of gluon saturation effects at forward/backward rapidities. One can describe the experimental data for J/ψ production within model uncertainties with color-singlet component only. Therefore our theoretical results leave only a relatively small room for the color-octet contributions.