Inclusive J/ψ production at e+e- colliders -: art. no. 034013

Inclusive J/psi production in e(+)e(-) annihilation is studied in the framework of NRQCD. We first review the leading-order calculations of the cross sections for e(+)e(-)-->J/psic (c) over bar and e(+)e(-)-->J/psigg and find that their ratio is about 1:1.5 at rootssimilar or equal to10 GeV. This result is in conflict with the current measurements by the Belle Collaboration, which finds that the process e(+)e(-)-->J/psic (c) over bar accounts for about 2/3 of all the prompt J/psi's. We find that the discrepancy problems in the total rate as well as in the J/psi momentum distributions can be resolved by postulating a large renormalization K factor (Ksimilar or equal to4) for the J/psic (c) over bar cross section and by taking into account collinear suppression in the end-point energy region of J/psigg production. Detailed studies of the model predictions in terms of the density matrix are performed and various momentum and angular distributions are presented as functions of the K factors. These distributions can be used to determine the normalizations of each subprocess provided that the production and decay angular distributions do not alter much by higher-order corrections.