The $\Lambda$(1600): A Strange Hybrid Baryon

Abstract

We use the method of QCD sum rules to investigate a possible hybrid baryon with the quantum numbers of the $\Lambda$. Using a current composed of uds quarks in a color octet and a gluon, a strange hybrid, the ${\Lambda }_H$ is found about 500 MeV above the $\Lambda$, and we identify it as the $\Lambda (1600)$. Using our sigma/glueball model we predict a large branching fraction for the ${\Lambda }_H\to \Lambda +\sigma (\pi \pi$ resonance), and the experimental search for this decay mode could provide a test of the hybrid nature of the $/Lambda(1600)$.

Comments: Revtex file, 3 Figures