The measurements of $\pi\Sigma$ mass distributions in the $\gamma p \rightarrow K^{+}\pi\Sigma$ photoproduction reaction [1] probe the energy region of the $\Lambda(1405)$ resonance, just below the $\bar{K}N$ threshold, and provide new challenges for the theoretical models of $\pi\Sigma - \bar{K}N$ coupled channels interactions. Adopting the photoproduction model presented in [2, 3] and the...
In the KbarN-piSigma coupled-channel system, two resonance states of the Lambda(1405) and Lambda(1380) states are considered to appear in the same physical Riemann sheets. To investigate the origin of these states, the detailed knowledge on the interaction is required. In this talk, we discuss the pole positions at the unphysical quark masses which can be accessed in the lattice QCD...