2001/12/31 by Michael Klasen, M. Klasen, B. A. Kniehl +5 · 10 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevlett.89.032001
published as Phys.Rev.Lett.89:032001,2002 · 11 pages (Latex), 3 figures (Postscript); updated experimental data included, references added, accepted for publication in Phys. Rev. Lett
arxiv created 2002/06/13 · openalex publication_date 2002/06/28 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present theoretical predictions for the transverse-momentum distribution of J/psi mesons promptly produced in gammagamma collisions within the factorization formalism of nonrelativistic quantum chromodynamics, including the contributions from both direct and resolved photons, and we perform a conservative error analysis. The fraction of J/psi mesons from decays of bottom-flavored hadrons is estimated to be negligibly small. New data taken by the DELPHI Collaboration at LEP2 nicely confirm these predictions, while they disfavor those obtained within the traditional color-singlet model.