Three body resonances in two meson-one baryon systems

TL;DR

This paper identifies new three-body resonances in meson-baryon systems by solving Faddeev equations with chiral unitary interactions, matching observed baryon resonances in the 1500-1800 MeV range.

Contribution

It introduces a coupled channel Faddeev approach with chiral unitary inputs to predict three-body resonances matching known baryon states.

Findings

Four $\Sigma$ and three $\Lambda$ resonances found near 1500-1800 MeV.

Resonances closely match existing $S=-1$, $J^P=1/2^+$ baryon states.

Method successfully links two-body interactions to three-body resonance structures.

Abstract

We report four $\Sigma$'s and three $\Lambda$'s, in the 1500 - 1800 MeV region, as two meson - one baryon S-wave $(1/2)^+$ resonances. We solve Faddeev equations in the coupled channel approach. The invariant mass of one of the meson-baryon pairs and that of the three particles have been varied and peaks in the squared three body $T$-matrix have been found very close to the existing $S$ = -1, $J^P= 1/2^+$ low lying baryon resonances. The input two-body $t$-matrices for meson-meson and meson-baryon interaction have been calculated by solving the Bethe-Salpeter equation with the potentials obtained in the chiral unitary approach.