X(6200) as a compact tetraquark in the QCD string model
arXiv:2107.14182 · doi:10.1140/epjc/s10052-021-09511-z
Abstract
Recently the LHCb Collaboration announced the first observation of nontrivial structures in the double- mass spectrum in the mass range 6.2-7.2 GeV, and a theoretical coupled-channel analysis of these data performed in Phys. Rev. Lett. 126, 132001 (2021) evidenced the existence of a new state close to the double- threshold. Although its molecular interpretation seems the most plausible assumption, the present data do not exclude an admixture of a compact component in its wave function, for which a fully-charmed compact tetraquark is the most natural candidate. It is argued in this work that the QCD string model is compatible with the existence of a compact state bound by QCD forces just below the double- threshold. A nontrivial interplay of the quark dynamics associated with this compact state and the molecular dynamics provided by soft gluon exchanges between mesons is discussed and the physical is argued to be a shallow bound state, in agreement with the results of the aforementioned coupled-channel analysis of the LHCb data.
10 pages, 6 tables, 4 figures, to appear in Eur. Phys. J. C
References in corpus (9)
- states: masses, production, and decays
- Heavy tetraquarks in the relativistic quark model
- Interplay of quark and meson degrees of freedom in a near-threshold resonance
- Insights into the inner structures of the fully charmed tetraquark state
- Fully-heavy tetraquark production by interactions in hadronic collisions at the LHC
- Pair structure of heavy tetraquark systems
- Fully-charm tetraquarks:
- QCD string in excited heavy-light mesons and heavy-quark hybrids
- Doubly hidden molecules and tetraquarks states from QCD at NLO