Analysis of Λ(1405) production data in the π^-p → K⁰πΣ reaction at p_π = 1.69 GeV/c

We have been studying the (Σπ)⁰ mass distribution based on data from an old Hydrogen Bubble Chamber collected by Thomas et al. concerning the p(π^-, K⁰)Σπ reaction at p_π = 1.69 GeV/c. In this analysis we investigated the formation of the Λ(1405) state, using the Generalized Optical Theorem and T-matrix operator. We applied a combined transition operator, T_mix, which contains T₂₁ (=T_πΣ-KN) and T₂₂ (= T_πΣ-πΣ) due to the initial channel mixing in the Λ(1405) formation. We also considered a possible mixture of I = 0 and 1 in the wave function, as well as some background of the Σ(1385) population.