Investigation on the bottom analogs of the $T_{cc}^{+}$

Abstract

We investigate the doubly bottom state $T_{bb}^{-}$ composed of two bottom mesons with $J^P=1^{+}$. The potentials are obtained using the one-boson exchange model. With the heavy quark flavor symmetry, all the parameters in the model are determined by fitting the experimental data of doubly charmed state $T_{cc}^{+}$ from our previous work. Our analysis indicates that the isospin symmetry is well-preserved. We identify a deeply bound $T_{bb}^{-}$ state with quantum numbers $I(J^P)=0(1^{+})$, in contrast to the loosely bound $T_{cc}^{+}$. Additionally, we discover a resonant $T_{bb}^{-}$ state with $I(J^P)=1(1^{+})$. Furthermore, our investigation into the $\bar{B}{\bar{B}}^{\ast }$-${\bar{B}}^{\ast }{\bar{B}}^{\ast }$ coupled channel effect reveals its important impact. The binding energy of the bound $I(J^P)=0(1^{+})$ states becomes deeper, while the resonant $T_{bb}^{-}$ state with $I(J^P)=1(1^{+})$ remains nearly unchanged.

24 pages, 7 figures, add discussions on the pole trajectory of the heavy meson pairs and a I=1 DD* resonance, accepted for publication in PRD