Hadronic Few-Body Systems in Chiral Dynamics

Hadronic composite states are introduced as few-body systems in hadron physics. The I >(1405) resonance is a good example of the hadronic few-body systems. It has turned out that I >(1405) can be described by hadronic dynamics in a modern technology, which incorporates coupled channel unitarity framework and chiral dynamics. The idea of the hadronic composite state of I >(1405) is extended to kaonic few-body states. It is concluded that, due to the fact that K and N have similar interaction nature in s-wave couplings, there are few-body quasibound states with kaons systematically just below the break-up thresholds, like and , as well as I >(1405) as a quasibound state and f (0)(980) and a (0)(980) as (K) over bar K.