Associated Quarkonia Production in a Single Boson e^+e^- Annihilation

The production cross sections of charmonia, charmonium–bottomonium and bottomonia pairs in a single boson e^+e^- annihilation have been studied in a wide range of energies, which will be achieved at future e^+e^- colliders such as ILC and FCC. One-loop QCD corrections to QCD and EW contributions as well as their interference are considered. The both intermediate bosons γ and Z are taken into account.