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arXiv · 1802.01102

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

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.

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Pietro Faccioli, Carlos Lourenco, Mariana Araujo, Joao Seixas. 2018-02-04. Universal kinematic scaling as a probe of factorized long-distance effects in high-energy quarkonium production. https://doi.org/10.1140/epjc%2Fs10052-018-5610-x

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