Speaker
Description
The question whether exotic forms of hadronic matter such as four-quark states, hybrid states with excited gluon fields, or glueballs exist is one of the major open questions of the Standard Model and has been driving experiments and theory since the development of the quark model. In the light-meson sector, the focus lies mainly on the search for spin-exotic states, which have $J^{PC}$ quantum-number combinations that are forbidden for $q\bar{q}$ states in the non-relativistic limit. To find these states we need to explore the light-meson spectrum in great detail. Since excited light mesons often have large widths and are overlapping, the mapping of their spectrum is challenging and requires large quantities of data, which need to be analyzed using partial-wave analysis (PWA) techniques. In addition, most excited meson states decay into multi-particle hadronic final states, for which the PWA requires extensive modeling of the dynamics of the final-state hadrons. In this talk, I will report on recent partial-wave analysis results that shed new light on possible candidates for spin-exotic states. I will also touch on novel analysis techniques and the prospects for future progress.
