Direct Evidence for the Multiplet Assignments ofΛ(1520)andΛ(1405)

Abstract

A measurement has been made of the relative signs of the resonant $K^{-}p\to \Sigma \pi$ reaction amplitudes coming from partial waves corresponding to $\Sigma \mathrm{}\left(1385\right)\mathrm{}$, $\Lambda \mathrm{}\left(1405\right)\mathrm{}$, and $\Lambda \mathrm{}\left(1520\right)\mathrm{}$. From this it is shown that $\Lambda \mathrm{}\left(1405\right)\mathrm{}$ and $\Lambda \mathrm{}\left(1520\right)\mathrm{}$ are to be described as predominantly SU(3) singlets.