Production ofJ/ψ+cc¯through two photons ine+eannihilation

Abstract
We study the production of J/ψ+cc¯ in e+e annihilation through two virtual photons. The cross section is estimated to be 23 fb at s=10.6GeV, which is smaller by a factor of 6 than the calculated cross section for the same process but through one virtual photon. As a result, while the annihilation into two photons may be important for certain exclusive production processes, the big difference between the inclusive production cross section σ(e+eJ/ψ+cc¯)0.9pb observed by Belle and the current nonrelativistic QCD prediction of 0.15pb still remains very puzzling. We find, however, that as the center-of-mass energy increases (s>20GeV) the production through two virtual photons e+e2γ*J/ψ+cc¯ will prevail over that through one virtual photon, because in the former process the photon fragmentation into J/ψ and into the charmed quark pair becomes more important at higher energies.
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