On the nature of the Lambda(1405) as a superposition of two states

Abstract

We use recent data on the $K^{-}p\to {\pi }^0{\pi }^0{\Sigma }^0$ reaction with the ${\pi }^0{\Sigma }^0$ mass distribution of forming the $\Lambda (1405)$ with a peak at 1420 MeV and a relatively narrow width of $\Gamma =38$ MeV, together with those of the ${\pi }^{-}p\to K^0\pi \Sigma$ reaction to show that there are two $\Lambda (1405)$ states instead of one as so far assumed.

arXiv commentContribution to the PANIC05 Conference, Santa Fe, October 2005