Compositeness of hadron resonances in finite volume

Understand

We develop a theoretical framework to quantify the structure of unstable hadron resonances.

• With the help of the corresponding system in a finite volume, we define the compositeness of resonance states which can be interpreted as a probability.
• This framework is used to study the structure of the scalar mesons f_0(980) and a_0(980).
• In both mesons, the Kbar K component dominates about a half of the wave function.