Tensor states $\hat{I}\yen B_c^{\ast -}$ and $J/\ddot{I}ˆB_c^{\ast +}$

Abstract

Tensor states ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}=\hat{I}\yen B_c^{\ast -}$ and ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{c}}=J/\ddot{I}ˆB_c^{\ast +}$ are explored using techniques of QCD sum rule method. These hadronic molecules, composed of only heavy quarks, have asymmetric quark contents $bb\overline{b}\overline{c}$ and $cc\overline{c}\overline{b}$, respectively. The masses $m=(15864\pm 85)\mathrm{MeV}$ and $\tilde{m}=(9870\pm 82)\mathrm{MeV}$ prove that these structures are unstable against dissociations to constituent mesons. Full widths of molecules ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}$ and ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{c}}$ are calculated by considering their dominant and subleading decay channels. The subleading channels are processes generated by annihilations of $\overline{b}b$ and $\overline{c}c$ quarks. For the molecule ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}$ dominant decays are ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}\to \hat{I}\yen B_c^{\ast -}$ and ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}\to \hat{I}{\cdot }_b{B}_c^{-}$, whereas subleading channels are transformations to ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}\to B^{(\ast )-}{\overline{D}}^{(\ast )0}$ and ${\overline{B}}_{(s)}^{(\ast )0}{D}_{(s)}^{(\ast )-}$ mesons. In the lower limit ($l.l.$) of the mass $m=15779\mathrm{MeV}$ for ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}$ decay to $\hat{I}\yen B_c^{\ast -}$ mesons is forbidden. In the case of ${\mathcal{M}}_{\mathrm{T}}^{\mathrm{c}}$ we explore decays to $J/\ddot{I}ˆB_c^{\ast +}$, $\hat{I}{\cdot }_c{B}_c^{+}$, $B^{(\ast )+}{D}^{(\ast )0}$ and $B_{(s)}^{(\ast )0}{D}_{(s)}^{(\ast )+}$ mesons. Predictions $\hat{I}“[{\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}]=120_{-12}^{+17}\mathrm{MeV}$, $\hat{I}“[{\mathcal{M}}_{\mathrm{T}}^{\mathrm{b}}{]}_{l.l.}=(65\pm 7)\mathrm{MeV}$ and ...

12 Pages, 6 Figures and 2 Tables