Doubly Heavy Tetraquark Resonant States

Abstract

Spectrum of the doubly heavy tetraquarks, $bb\bar{q}\bar{q}$, is studied in a constituent quark model. Four-body problem is solved in a variational method where the real scaling technique is used to identify resonant states above the fall-apart decay thresholds. In addition to the two bound states that were reported in the previous study we have found several narrow resonant states above the $B{B}^{\ast }$ and $B^{\ast }{B}^{\ast }$ thresholds. Their structures are studied and are interpreted by the quark dynamics. A narrow resonance with spin-parity $J^P=1^{+}$ is found to be a mixed state of a compact tetraquark and a $B^{\ast }{B}^{\ast }$ scattering state. This is driven by a strong color Coulombic attraction between the $bb$ quarks. Negative-parity excited resonances with $J^P=0^{-}$, $1^{-}$ and $2^{-}$ form a triplet under the heavy-quark spin symmetry. It turns out that they share a similar structure to the $\lambda$-mode of a singly heavy baryon as a result of the strongly attractive correlation for the doubly heavy diquark.

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Cited by in corpus (7)

• An updated review of the new hadron states
• $T_{cc}^{+}$ and its partners
• Doubly heavy tetraquarks in an extended chromomagnetic model
• $T_{cc}^{+}$ and $X(3872)$ with the complex scaling method and $DD(\bar{D})\pi$ three-body effect
• Mass spectra of doubly heavy tetraquarks in diquark-antidiquark picture
• Double-heavy tetraquarks with strangeness in the chiral quark model
• Masses of doubly heavy tetraquarks $QQ\bar{n}\bar{q}$ with $J^P=1^{+}$