Exotics in the $\ddot{I}€D$ system

Abstract

In this proceedings we consider several states, namely the $D_{s0}^{\ast }(2317)$, $D_{s1}(2460)$, $D_0^{\ast }(2300)$ and $D_1(2430)$, which appear to defy description as simple quark-antiquark pairs. Theoretical input from unitarized chiral perturbation theory suggests they can be understood as emerging from Goldstone-Boson--$D$-meson scattering. We present results from an $SU(3)$ flavor-symmetric lattice QCD simulation at large pion masses suggesting that there exists a $\ddot{I}€D$ bound state in the flavor-sextet representation that cannot emerge for quark-antiquark states, but that appears naturally from the multiquark states. Moreover, we find repulsion in the [15] representation, which establishes the pattern predicted for the interactions of Goldstone bosons with $D$ mesons. This suggests these states may have the structure of hadronic molecules.

9 pages, 5 figures, Submitted to Proceedings of Science for LATTICE21. Based on work presented in arXiv:2106.15391. Acknowledgements updated