Λ*N bound state based on chiral dynamics

Dynamics of the two-body system of the Λ*=Λ(1405) and a nucleon is studied, with the properties of the Λ* being constrained by the chiral SU(3) dynamics. The interaction potential of the Λ*N system is constructed in a meson exchange model, where the coupling constants for the Λ* vertices are determined through the microscopic meson-baryon dynamics. For the description of the physical Λ(1405), we consider two Λ* states generated by the chiral low energy interactions in K-barN and πΣ channels. It is found that the Λ*N interactions are attractive in the total spin S=0 channel for both the Λ* states. Introducing the mixing of two Λ*'s, we obtain the ground state of the bound Λ*N system, which lies between the K-barNN threshold and the πΣN threshold. (author)