Speaker
Sergey Privalov
Description
We report measurements of the $e^+e^− \rightarrow B\bar{B}, B\bar{B}^*,$ and $B^*\bar{B}^*$ cross sections at four energies, 10653, 10701, 10746 and 10805 MeV, using data collected by the Belle II experiment. We reconstruct one $B$ meson in a large number of hadronic final states and use its momentum to identify the production process. In the first 2 − 5 MeV above $B\bar{B}^*$ threshold, the $e^+e^− \rightarrow B^*\bar{B}^*$ cross section increases rapidly. This may indicate the presence of a pole close to the threshold.
