Double-charm production e+e-→J/ψ+cc̄ at B factories with next-to-leading-order QCD corrections

The inclusive J/ψ production in e+e-→J/ψcc̄ 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 ψ(2S) as well as χcJ] and the two-photon contributions, and find that the discrepancy between theory and experiment can be largely removed.