Hadronic molecules composed of a doubly charmed tetraquark state and a charmed meson

The three pentaquark states, P-c(4312), P-c(4440) and P-c(4457), discovered by the LHCb Collaboration in 2019, can be arranged into a complete heavy quark spin symmetry multiplet of hadronic molecules of (D) over bar (()*()) Sigma(()(c)*()). In the heavy quark mass limit, the Sigma(()(c)*()) baryons can be related to the doubly charmed tetraquark states of isospin 1, i.e., T-(c) over bar(c) over bar(()*()) (T-(c) over bar(c) over bar(0), T-(c) over bar(c) over bar(1), T-(c) over bar(c) over bar(2)), via heavy antiquark diquark symmetry, which dictates that the (D) over bar (()*()) Sigma(()(c)*()) interactions are the same as the (D) over bar (()*()) T-(c) over bar(c) over bar(()*()) interactions up to heavy antiquark diquark symmetry breakings. In this work, we employ the contact-range effective field theory to systematically study the (D) over bar (()*()) T-(c) over bar(c) over bar(()*()) systems, and we show the existence of a complete heavy quark spin symmetry multiplet of hadronic molecules composed of a doubly charmed tetraquark state and a charmed meson. These are a new kind of hadronic molecules and, if discovered, can lead to a better understanding of the many exotic hadrons discovered so far. In addition, we summarise the triply charmed hexaquark states formed by different combinations of hadrons. In particular, we show that (Omega) over bar (ccc)p system can bind by the Coulomb force, which is analogous to a hydrogenlike atom.

Automated summary

This study systematically investigates the heavy quark spin symmetry multiplet and its impact on other exotic hadrons using contact-range effective field theory. Additionally, it summarizes the triply charmed hexaquark states formed by different combinations of hadrons.