While a majority of the community agrees that the XYZ states have a non-q̄q nature, the internal structure of these states is not yet understood. To deepen our understanding in this field, additional experimental and theoretical studies are needed. For example, complete spin multiplets should be studied; to distinguish true resonance signals from kinematic effects, the confirmation of states in different experiments is needed; resonance shape measurements are compulsory to access the long ranged parts of the exotic wave functions.
At present most experimental information comes from Belle (II) (Japan), BESIII (China) and LHCb (CERN). The gluon-rich process of pp̄ annihilation as it will be available for the upcoming PANDA experiment at the FAIR facility (Germany) promises new and complementary insights. The workshop focusses on the status and future perspectives in the field of exotic hadrons in the heavy quarkonium mass region.
| Experiment | Talk (title) |
| Peter Braun-Munzinger | "ALICE results on XYZ" |
| Sean Dobbs | "Study charmonia and hybrids with GlueX" |
| Simon Eidelmann | "Future relevant experiments" |
| Alexey Guskov | "COMPASS results on XYZ states" |
| Zhiqing Liu | "BESIII results on X and Z states" |
| Roman Mizuk | "Belle(II) XYZ results in the B sector" |
| Sebastian Neubert | "LHCb results on exotic charmonia" |
| Marco Pappagallo | "LHCb results on (ordinary) charmonia and bottomonia" |
| Cheng-Ping Shen | "Belle(II) XYZ results in the charm sector" |
| Chengzeng Yuan | "BESIII results on vector Y states" |
| Theory | Talk (title) |
| Eric Braaten | "Production of X(3872)" |
| Nora Brambilla | "Effective field theories for regular quarkonia and exotics" |
| Feng-Kun Guo | "Triangle Singularities" |
| Luciano Maiani | "Tetraquarks" |
| Ulf-G. Meißner | "Hadronic Molecules" |
| Alessandro Pilloni | "Production of X(3872)" |
| Sinead Ryan | "Lattice QCD in the doubly heavy sector" |
| Marc Vanderhaegen | "Inclusion of pi pi interactions in heavy meson decays" |