Study on e⁺e^- → B^(∗)(equation presented)^(∗) and Υ(5S) → Υ(1S,2S)η^(')

We report the first measurement of exclusive cross sections for e⁺e^- → B(equation presented), e⁺e^- → B(equation presented)^∗, and e⁺e^- → B^∗ (equation presented)^∗ in the energy range from 10.63 GeV to 11.02 GeV. The B mesons are fully reconstructed in a large number of hadronic final states, and the three channels are distinguished using the beam-energy-constrained mass variable. For each channel, the cross section shows an oscillatory behavior, with multiple maxima and minima. The final results on Υ(5S) → Υ(1S, 2S)η and Υ(5S) → Υ(1S)η' branching fractions are also presented. All these results are based on data collected by the Belle experiment at the KEKB asymmetric-energy e⁺e^- collider.