Relatore
Descrizione
The discovery of the X, Y, Z states in the (hidden) charm meson sector first by Belle, and the PC baryon states by LHCb revealed the existence of multi-quark objects beyond the simple quarkantiquark or 3-quark valence configurations. If the emergence of such multi-quark structures was a general feature of QCD, then related structures should appear in the uds-sector as well. The BGOOD experiment at the ELSA electron accelerator of Bonn University is exactly devoted to investigate such possible baryonic structures in meson photoproduction. Particular attention is paid to threshold effects in associated KY photoproduction. I will discuss recent results which include the archetypal meson-baryon 5-quark hyperon Λ(1405), the hypothesised N(2030/2080) as the strange-sector partners of the charm-sector PC(4380/4450) pentaquarks, and an intriguing cusp effect at the K Σ(1385) threshold.
This project received funding from the DFG (Project no 50165297 and 405882627), from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 824093, and from the Land NRW.
