Spin Partners of the $B^{(\ast )}{\bar{B}}^{(\ast )}$ resonances with a different approach than the Breit-Wigner parameterization

Abstract

In general, resonances are obtained by the Breit-Wigner parameterization. However, it is not entirely appropriate to use this parameterization with near-threshold resonances such as the $Z_b(10610)$ and the $Z_b(10650)$, as Breit-Wigner does not contain the threshold effect. To eliminate this defect, a recently proposed alternative distribution, the Sill, is used to predict possible heavy quark spin symmetry partners of the $Z_b(10610)$ and the $Z_b(10650)$. With the Sill values of the $Z_b(10650)$ and the $Z_b(10610)$ states, assuming these exotics generate molecular states consisting of contact and a pion exchange potential, heavy quark spin symmetry partners are examined with $S$ and $D$-wave contributions. In the light of the Sill type resonance approach, all the partners are found as bound states.

8 pages, 3 tables, Accepted for publication in EPJ A

References in corpus (10)

• The Heavy Quark Spin Symmetry Partners of the X(3872)
• $Z_b$ and $Z_c$ Exotic States as Coupled Channel Cusps
• Confirming the molecular nature of the $Z_b(10610)$ and the $Z_b(10650)$
• BB Potentials in Quenched Lattice QCD
• Study of $B{\bar{B}}^{\ast }$ and $B^{\ast }{\bar{B}}^{\ast }$ interactions in $I=1$ and relationship to the $Z_b(10610)$, $Z_b(10650)$ states
• Molecular states from $D^{(\ast )}{\bar{D}}^{(\ast )}/B^{(\ast )}{\bar{B}}^{(\ast )}$ and $D^{(\ast )}{D}^{(\ast )}/{\bar{B}}^{(\ast )}{\bar{B}}^{(\ast )}$ interactions
• Strong D* -> D+pi and B* -> B+pi couplings
• Precision lattice QCD computation of the $B^{\ast }B\pi$ coupling
• A simple alternative to the Breit-Wigner distribution
• Systematic Study of Hadronic Molecules in the Heavy-Quark Sector