Towards Meson Spectroscopy Instead of Bump Hunting

Understand

Mesonic resonances are generally observed in data as narrow, moderately broad, or wide peaks in scattering or production processes.

• In the eyes of nearly all experimentalists, any suchlike bump is a true resonance as soon as its statistical significance exceeds certain minimal values.
• However, this simple point of view ignores possible effects from competing hadronic channels and the opening of the corresponding thresholds.
• On the other hand, most theoretical hadron-model builders consider mesons merely bound states of a quark and an antiquark, or of more exotic combinations sometimes involving valence gluons as well.