Peak shifts due to $B^{(*)}-\bar{B}^{(*)}$ rescattering in $Υ(5S)$ dipion transitions
Abstract
Description
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 $Υ(5S)\to B^{(*)}\bar{B}^{(*)}$ and $B^{(*)}\bar{B}^{(*)}\to Υ(1S,2S,3S)π^+π^-$. We find that the energy distributions of $Υ(1S,2S,3S)π^+π^-$ markedly differ from that of $Υ(5S)\to B^{(*)}\bar{B}^{(*)}$. 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.
Version published in PRD, energy dependence of the total width in Eq.(12) restored and corresponding figure changed, more discussion and clarification added
Version published in PRD, energy dependence of the total width in Eq.(12) restored and corresponding figure changed, more discussion and clarification added