O(α_Sv²) correction to J/ψ plus η_c production in e⁺e^- annihilation at √s=10.6 GeV

Based on the nonrelativistic QCD factorization approach, O(α_sv²) corrections to J/ψ plus η_c production in e⁺e⁻ annihilation at √s=10.6GeV are calculated in this work. The numerical results show that the correction at α_sv² order is only about a few percent of the total theoretical result. This indicates that the perturbative expansions become convergent and {that a} higher order correction will be smaller. The uncertainties from the long-distance matrix elements, renormalization scale and the measurement in the experiment are also discussed. Our result is in agreement with the previous result by Jia