Two-body wave functions, compositeness, and the internal structure of dynamically generated resonances

Sekihara, Takayasu; Hyodo, Tetsuo*; Jido, Daisuke*; Yamagata-Sekihara, Junko*; Yasui, Shigehiro*

In this contribution, I introduce the physical meaning of the compositeness, its expression, and theoretical evaluation in effective models. In particular, we show that the two-body wave function of the bound state corresponds to the residue of the scattering amplitude at the bound state pole, which means that solving the Lippmann-Schwinger equation at the bound state pole is equivalent to evaluating the two-body wave function of the bound state. Then, we evaluate the compositeness for the so-called dynamically generated resonances in the chiral unitary approach, such as , , and , and investigate their internal structure in terms of the hadronic molecular components.