Enhanced mixing of partial waves near threshold for heavy meson pairs and properties of $Z_b(10610)$ and $Z_b(10650)$ resonances

Abstract

The mixing of $S-D$ partial waves for the heavy meson pairs in the decays ${\rm Y}(5S)\to [B^{\ast }\bar{B}+c.c.]\pi$ and ${\rm Y}(5S)\to B^{\ast }{\bar{B}}^{\ast }\pi$ is considered. It is argued that this mixing, enhanced by the heavy meson mass, is calculable as dominated by a rescattering through pion exchange if the production of the heavy mesons is dominated by $S$-wave `molecular' resonances $Z_b(10610)$ and $Z_b(10650)$. The effect of the mixing grows with the c.m. energy $E$ in each channel over the threshold, and may reach $10÷20$% in the rate at the upper end of applicability of the discussed approach, $E\sim 15$MeV. It is also argued that the mixing is likely to reach maximum at energy approximately equal to the mass gap between the thresholds.

arXiv comment8 pages, 3 figures

References in corpus (7)

• Observation of two charged bottomonium-like resonances in Y(5S) decays
• Heavy quark spin structure in Z_b resonances
• $Z_b(10610{)}^{\pm }$ and $Z_b(10650{)}^{\pm }$ as the $B^{\ast }\bar{B}$ and $B^{\ast }{\bar{B}}^{\ast }$ molecular states
• First Measurement of Gamma(D*+) and Precision Measurement of m_D*+ - m_D0
• Coupled-channel analysis of the possible $D^{(\ast )}{D}^{(\ast )}$, ${\bar{B}}^{(\ast )}{\bar{B}}^{(\ast )}$ and $D^{(\ast )}{\bar{B}}^{(\ast )}$ molecular states
• Heavy Quark Symmetry Predictions for Weakly Bound B-Meson Molecules
• Study of Three-Body Y(10860) Decays

Cited by in corpus (20)

• The hidden-charm pentaquark and tetraquark states
• Possible assignments of the $X(3872)$, $Z_c(3900)$ and $Z_b(10610)$ as axial-vector molecular states
• Reanalysis of the $Y(3940)$, $Y(4140)$, $Z_c(4020)$, $Z_c(4025)$ and $Z_b(10650)$ as molecular states with QCD sum rules
• The $Z_b(10610)$ and $Z_b(10650)$ as axial-vector tetraquark states in the QCD sum rules
• Confirming the molecular nature of the $Z_b(10610)$ and the $Z_b(10650)$
• Heavy hadronic molecules with pion exchange and quark core couplings: a guide for practitioners
• Interplay of quark and meson degrees of freedom in near-threshold states: A practical parametrisation for line shapes
• More hidden heavy quarkonium molecules and their discovery decay modes
• Hunting for the X_b via Radiative Decays
• Enhanced breaking of heavy quark spin symmetry
• Fully Heavy Tetraquark $bb\bar{c}\bar{c}$: Lifetimes and Weak Decays
• Hunting for the $X_b$ via hidden bottomonium decays
• Weak Decays of Triply Heavy Tetraquarks $b\bar{c}b\bar{q}$
• Exploring the ${\rm Y}(4S,5S,6S)\to h_b(1P)\eta$ hidden-bottom hadronic transitions
• Weak Decays of Doubly-Heavy Tetraquarks $b\bar{c}q\bar{q}$
• $D$ wave bottomonia production from $Z_b^{(\prime )}$ decay
• Mixing of partial waves near $B^{\ast }{\bar{B}}^{\ast }$ threshold in $e^{+}{e}^{-}$ annihilation
• Modification by pion exchange of near threshold resonance line shape in open heavy flavor channel
• Evasion of HSR in the charmless decays of excited $P$-wave charmonia
• Decays of ${\rm Y}(10860)$ and ${\rm Y}(10753)$ into $\omega {\chi }_{bJ}$