Production and polarization of S -wave quarkonia in potential nonrelativistic QCD

Abstract

Based on the potential nonrelativistic QCD formalism, we compute the nonrelativistic QCD long-distance matrix elements (LDMEs) for inclusive production of $S$-wave heavy quarkonia. This greatly reduces the number of nonperturbative unknowns and brings in a substantial enhancement in the predictive power of the nonrelativistic QCD factorization formalism. We obtain improved determinations of the LDMEs and find cross sections and polarizations of $J/\ensuremath{\psi}$, $\ensuremath{\psi}(2S)$, and excited $\mathrm{\ensuremath{\Upsilon}}$ states that agree well with LHC data. Our results may have important implications in pinning down the heavy quarkonium production mechanism.