$Z_b(10610{)}^{\pm }$ and $Z_b(10650{)}^{\pm }$ as the $B^{\ast }\bar{B}$ and $B^{\ast }{\bar{B}}^{\ast }$ molecular states

Abstract

In the framework of the one-boson-exchange model, we have studied the interaction of the $B^{\ast }\bar{B}$ and $B^{\ast }{\bar{B}}^{\ast }$ system. After considering the S-wave and D-wave mixing, we notice that both $Z_b(10610{)}^{\pm }$ and $Z_b(10650{)}^{\pm }$ can be interpreted as the $B^{\ast }\bar{B}$ and $B^{\ast }{\bar{B}}^{\ast }$ molecular states quite naturally. Within the same framework, there also exist several molecular charmonia including X(3872) and several other molecular bottomonia, which are the partners of $Z_b(10610)$ and $Z_b(10650)$. The long-range one-pion-exchange force alone is strong enough to form these loosely bound molecular states, which ensures the numerical results quite model-independent and robust.

Comments: 11 pages, 6 tables