QCD factorization for hadronic quarkonium production at high $p_T$

Abstract

Heavy quarkonium production at high transverse momentum ( p_T p T ) in hadronic collisions is explored in the QCD factorization approach. We find that the leading power in the 1/p_T 1 / p T expansion is responsible for high p_T p T regime, while the next-to-leading power contribution is necessary for the low p_T p T region. We present the first numerical analysis of the scale evolution of coupled twist-2 and twist-4 fragmentation functions (FFs) for heavy quarkonium production and demonstrate that the QCD factorization approach is capable of describing the p_T p T spectrum of hadronic J/\psi J / ψ production at the LHC.