One-Loop Corrections To The Processes E(+)E(-) -> Gamma, Z -> J/Psi Eta C And E(+)E- -> Z -> J/Psi J/Psi

The cross sections of J/psi eta(c) and J/psi J/psi production in e(+)e(-) annihilation are calculated at a one-loop accuracy near Z-boson pole and at higher energies as well. Both intermediate bosons, gamma and Z, are included. It is found that at Z mass, the next-to-leading contribution increases the production cross sections by a factor of 3.5.