Quarkonium production at the LHC: A data-driven analysis of remarkably simple experimental patterns

Abstract

The LHC quarkonium production data reveal a startling observation: the J/ψ, ψ(2S), χc1, χc2 and ϒ(nS) pT-differential cross sections in the central rapidity region are compatible with one universal momentum scaling pattern. Considering also the absence of strong polarizations of directly and indirectly produced S-wave mesons, we conclude that there is currently no evidence of a dependence of the partonic production mechanisms on the quantum numbers and mass of the final state. The experimental observations supporting this universal production scenario are remarkably significant, as shown by a new analysis approach, unbiased by specific theoretical calculations of partonic cross sections, which are only considered a posteriori, in comparisons with the data-driven results. Keywords: Quarkonium, Polarization, NRQCD, QCD, Hadron formation