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تسجيل مستخدم جديدHeavy Holographic Exotics: Tetraquarks as Efimov States
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We provide a holographic description of non-strange multiquark exotics as compact topological molecules by binding heavy-light mesons to a tunneling configuration in D8-D$bar 8$ that is homotopic to the vacuum state with fixed Chern-Simons number. In the tunneling process, the heavy-light mesons transmute to fermions. Their binding is generic and arises from a trade-off between the dipole attraction induced by the Chern-Simons term and the U(1) fermionic repulsion. In the heavy quark limit, the open-flavor tetraquark exotics $QQbar qbar q$ and $bar Qbar Q qq$, emerge as bound Efimov states in a degenerate multiplet $IJ^pi=(00^+ , 01^+)$ with opposite intrinsic Chern-Simons numbers $pm frac 12$. The hidden-flavor tetraquark exotics such as $Qbar Q qbar q$, $QQbar Qbar q$ and $QQbar Qbar Q$ as compact topological molecules are unbound. Other exotics are also discussed.
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