Λ(1405) photoproduction at SPring-8/LEPS Original Research Article

The nature of Λ(1405) hyperon is still mystery for the distinction between an unstable View the MathML source bound state and L = 1 SU(3)-singlet three quark state coupled with the S-wave View the MathML source channels. Recent theoretical works predict its lineshape to be different in terms of different charge combinations of the πΣ decay channels in the context of chiral dynamics plus final-state interaction. We have measured the lineshape of Λ(1405) in charged πΣ channels through p(γ, K+π)Σ reaction at 1.5–2.4 GeV. The observed lineshapes in π−Σ+ and π+Σ− channels are different, which implies that the Λ(1405) could be interpreted as a bound-state of meson-baryon states.