2003/06/21 by B. L. Ioffe, B.L. Ioffe, D. E. Kharzeev +1 · 3 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.69.014016
published as Phys.Rev. D69 (2004) 014016 · 3 pages, 2 figures
arxiv created 2003/06/21 · openalex publication_date 2004/01/30 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Recently, several surprising experimental observations in the production of heavy quarkonium have been reported. In e+e^\ensuremath- annihilation at √(s)=10.6 GeV, the Belle Collaboration finds that J/\ensuremathψ mesons are predominantly produced in association with an extra cc pair, with \ensuremathσ(e+e^\ensuremath-\ensuremath→J/\ensuremathψcc)/\ensuremathσ(e+e^\ensuremath-\ensuremath→J/\ensuremathψX)=0.59_\ensuremath-0.13+0.15\ifmmode±\else\textpm\fi0.12, and the BaBar Collaboration reports that the produced J/\ensuremathψ's have mostly longitudinal polarization. In pp collisions at the Fermilab Tevatron, the CDF Collaboration reported an excess of J/\ensuremathψ and \ensuremathψ^\ensuremath' mesons at high p_\ensuremath⊥ over the perturbative QCD predictions; the nonperturbative approach of nonrelativistic QCD can accommodate the magnitude of the production cross section but not the observed experimental polarization of quarkonia. In this note we propose possible solutions to these puzzles and devise further experimental tests.