Eur. Phys. J. C (2018) 78: 118
https://doi.org/10.1140/epjc/s10052-018-5610-x

Regular Article - Experimental Physics

Universal kinematic scaling as a probe of factorized long-distance effects in high-energy quarkonium production

¹ LIP and IST, Lisbon, Portugal
² CERN, Geneva, Switzerland

^* e-mail: pietro.faccioli@cern.ch
^** e-mail: carlos.lourenco@cern.ch

Received: 15 December 2017
Accepted: 31 January 2018
Published online: 9 February 2018

Abstract

Dimensional analysis reveals general kinematic scaling rules for the momentum, mass, and energy dependence of Drell–Yan and quarkonium cross sections. Their application to mid-rapidity LHC data provides strong experimental evidence supporting the validity of the factorization ansatz, a cornerstone of non-relativistic QCD, still lacking theoretical demonstration. Moreover, data-driven patterns emerge for the factorizable long-distance bound-state formation effects, including a remarkable correlation between the S-wave quarkonium cross sections and their binding energies. Assuming that this scaling can be extended to the P-wave case, we obtain precise predictions for the not yet measured feed-down fractions, thereby providing a complete picture of the charmonium and bottomonium feed-down structure. This is crucial information for quantitative interpretations of quarkonium production data, including studies of the suppression patterns measured in nucleus-nucleus collisions.