Double-charm production e+e- -->J/psi + cc at B factories with next-to-leading-order QCD corrections.
The inclusive J/psi production in e;{+}e;{-}-->J/psicc at B factories is one of the most challenging open problems in heavy quarkonium physics. The observed cross section of this double-charm production process is larger than existing leading order (LO) QCD predictions by a factor of 5. In the nonrelativistic QCD (NRQCD) factorization formalism, we calculate the next-to-leading order (NLO) QCD virtual and real corrections to this process, and find that these corrections can substantially enhance the cross section with a K factor of about 1.8. We further take into account the feeddown contributions from higher charmonium states [mainly the psi(2S) as well as chi_{cJ}] and the two-photon contributions, and find that the discrepancy between theory and experiment can be largely removed.
Zhang
Yu-Jie
YJ
Department of Physics, Peking University, Beijing 100871, People's Republic of China.
Chao
Kuang-Ta
KT
D003198:Computer Simulation; D019471:Elementary Particle Interactions; D008962:Models, Theoretical; D009686:Nuclear Physics; D017785:Photons; D011789:Quantum Theory