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 $J/\psi$, $\psi (2S)$, and excited ${\rm Y}$ states that agree well with LHC data. Our results may have important implications in pinning down the heavy quarkonium production mechanism.

Comments: 6 pages, 2 figures, 2 tables, minor corrections, version published as a Letter in Phys. Rev. D