Scalar exotic mesons $bb\overline{c}\overline{c}$

Abstract

Properties of doubly charged scalar tetraquarks $bb\overline{c}\overline{c}$ are investigated in the framework of the QCD sum rule method. We model them as diquark-antidiquark states $X_1$ and $X_2$ built of axial-vector and pseudoscalar diquarks, respectively. The masses and current couplings of these particles are computed using the QCD two-point sum rule method. Results $m_1=(12715\pm 80)\mathrm{MeV}$ and $m_2=(13370\pm 95)\mathrm{MeV}$ obtained for the masses of these particles are used to determine their kinematically allowed decay modes. The full width ${\Gamma }_1$ of the state $X_1$ is evaluated by taking into account its strong decays to mesons $2B_c^{-}$, and $2B_c^{\ast -}$. The processes $X_2\to 2B_c^{-}$, $2B_c^{\ast -}$ and $B_c^{-}{B}_c^{-}(2S)$ are employed to estimate ${\Gamma }_2$. Predictions obtained for the full widths ${\Gamma }_1=(63\pm 12)\mathrm{MeV}$ and ${\Gamma }_2=(79\pm 14)\mathrm{MeV}$ of these structures and their masses may be utilized in experimental studies of fully heavy resonances.

Comments: 12 Pages and 4 Figures