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The spectroscopic parameters and decay channels of the scalar tetraquark $ T_{bb;overline{u}overline{s}}^{-}$ (in what follows $T_{b:overline{s} }^{-} $) are investigated. The mass and coupling of the $T_{b:s}^{-}$ are calculated using the two-point sum rules by taking into account quark, gluon and mixed vacuum condensates up to dimension 10. Our result for its mass $m=(10250 pm 270)~mathrm{MeV}$ demonstrates that $T_{b:overline{s}}^{-} $ is stable against the strong and electromagnetic decays. Therefore to find the width and mean lifetime of the $T_{b:overline{s}}^{-}$, we explore its dominant weak decays generated by the transition $b to W^{-}c$. These channels embrace the semileptonic decay $T_{b:overline{s}}^{-} to Z_{bc;overline{u}overline{s}}^{0}loverline{ u }_{l}$ and nonleptonic modes $T_{b:overline{s}}^{-} to Z_{bc;overline{ u}overline{s}}^{0}pi^{-}(K^{-}, D^{-}, D_s^{-})$, which at the final state contain the scalar tetraquark $Z_{bc;overline{u}overline{s}}^{0}$. Key quantities to compute partial widths of the weak decays are the form factors $G_1(q^2)$ and $G_2(q^2)$: they determine differential rate $dGamma/dq^2$ of the semileptonic and partial widths of the nonleptonic processes, respectively. These form factors are extracted from relevant three-point sum rules at momentum transfers $q^2$ accessible for such analysis. By means of the fit functions $F_{1(2)}(q^2)$ they are extrapolated to cover the whole integration region $m_l^{2}leq q2leq(m-widetilde m)^2$, where $widetilde m$ is the mass of $Z_{bc;overline{u}overline{s}}^{0}$. Predictions for the full width $Gamma _{mathrm{full}}=(15.21pm 2.59)times 10^{-10}~mathrm{ MeV}$ and mean lifetime $4.33_{-0.63}^{+0.89}times 10^{-13}~mathrm{s}$ of the $T_{b:s}^{-} $ are useful for experimental and theoretical investigations of this exotic meson.
The mass and coupling of the scalar tetraquark $T_{bb;overline{u}overline{d }}^{-}$ (hereafter $T_{b:overline{d}}^{-} $) are calculated in the context of the QCD two-point sum rule method. In computations we take into account effects of various quark
The spectroscopic parameters and decay channels of the axial-vector tetraquark $T_{bb;overline{u}overline{s}}^{-}$ (in what follows, $T_{b: overline{s}}^{mathrm{AV}}$) are explored using the quantum chromodynamics (QCD) sum rule method. The mass and
The weak decays of the axial-vector tetraquark $T_{bb;bar{u} bar{d}}^{-}$ to the scalar state $Z_{bc;bar{u} bar{d}}^{0}$ are investigated using the QCD three-point sum rule approach. In order to explore the process $T_{bb; bar{u} bar{d}}^{-} to Z_{bc
The mass and coupling of the doubly charmed $J^P=0^{-}$ diquark-antidiquark states $T_{cc;bar{s} bar{s}}^{++}$ and $T_{cc;bar{d} bar{s}}^{++}$ that bear two units of the electric charge are calculated by means of QCD two-point sum rule method. Comput
In this work, we study systematically the mass splittings of the $qqbar{Q}bar{Q}$ ($q=u$, $d$, $s$ and $Q=c$, $b$) tetraquark states with the color-magnetic interaction by considering color mixing effects and estimate roughly their masses. We find th