Chiral Dynamics of Low-Energy Kaon-Baryon Interactions with Explicit Resonance

Abstract

The processes involving low energy $\bar{K}N$ and $Yπ$ interactions (where $Y= Σ$ or $Λ$) are studied in the framework of heavy baryon chiral perturbation theory with the $Λ$(1405) resonance appearing as an independent field. The leading and next-to-leading terms in the chiral expansion are taken into account. We show that an approach which explicitly includes the $Λ$(1405) resonance as an elementary quantum field gives reasonable descriptions of both the threshold branching ratios and the energy dependence of total cross sections.