Speaker
Description
The hadron spectrum offers deep insights into the strong force, the origin of hadronic mass, quark confinement, and the transition from quarks and gluons to observable particles. While the quark structure of hadrons is well understood, most of their mass arises from the binding force rather than the quarks themselves — this is a largely uncharted territory whose exploration has been attracting for decades many experimental efforts.
Meson spectroscopy provides a valuable framework for studying quark interactions and the role of gluons. This includes identifying conventional mesons and searching for unconventional states such as multiquark aggregates, hybrids, and glueballs. States with exotic quantum numbers present unique opportunities for discovery, yet many observed candidates exhibit ordinary quantum numbers. This complicates their interpretation due to large widths and shared decay patterns within overlapping mass ranges.
This talk will review recent experimental progress in light meson spectroscopy, studying hadrons composed by the lightest (u, d, s) quarks only in the mass range below 2 GeV/c². It will highlight results from various processes, including e+e- and Nucleon-Antinucleon annihilation, hadron scattering, and electro- and photoproduction. Especially in the latest years advances in analysis techniques and lattice QCD have been instrumental, offering new tools to disentangle these complex phenomena for a deeper understanding of the strong interaction and QCD’s non-perturbative regime: A short description of some expectations from theory will be discussed, related to the most recent experimental observations.
