A pentaquark model for Λ(1405) Original Research Article

We study a pentaquark model of the negative parity hyperon Λ(1405). We choose a specific quark configuration for trial, and use the perturbative chiral quark model extended to four quarks and one anti-quark system. We calculate a σ-term and a scalar form factor of the hyperon and demonstrate their usefulness to study the nature of the hyperon.