Chiral coupled channel dynamics of the Lambda(1520) and the K-P -> pi0 pi0 Lambda reaction

Abstract

We study the $Λ(1520)D_{03}$ in a chiral coupled channel approach. This resonance appears as dynamically generated from the interaction of the decuplet of baryons and the octet of mesons in s-wave, and its treatment is improved here with the phenomenological inclusion of the $\bar{K} N$ and $πΣ$ channels in d-wave. Since the most important building block in the $Λ(1520)$ is the $π\Sgs(1385)P_{13}$ channel, we study the $K^- p \to π\Sgs(1385) (π^0 Λ)$ reaction in the region of the $Λ(1520)$ and above, and compare the results with recent experimental data. With the coupling of the $Λ(1520)$ to the $π\Sgs$ channel predicted by the theory we find a cross section in good agreement with the data and there is as well agreement for the invariant mass distributions which show a neat peak for the $\Sgs(1385)$ in the $(π^0 Λ)$ spectrum. Predictions are made of a strong $Λ(1520)$ resonant peak of the cross section, as a function of the $K^-$ momentum, in the region below the measured data which, if confirmed experimentally, would give a stronger support to the idea of the $Λ(1520)$ as a dynamically generated resonance.