Peak shifts due to B(*)-B(*) rescattering in Υ(5S) dipion transitions

We study the energy distributions of dipion transitions Υ(5S) to Υ(1S,2S,3S)π+π- in the final-state rescattering model. Since the Υ(5S) is well above the open bottom thresholds, the dipion transitions are expected to mainly proceed through the real processes Υ(5S)→B(*)B(*) and B(*)B(*)→Υ(1S,2S,3S)π+π-. We find that the energy distributions of Υ(1S,2S,3S)π+π- markedly differ from that of Υ(5S)→B(*)B(*). In particular, the resonance peak will be pushed up by about 7-20 MeV for these dipion transitions relative to the main hadronic decay modes. These predictions can be used to test the final-state rescattering mechanism in hadronic transitions for heavy quarkonia above the open flavor thresholds.