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