We study the decays Ω- → Ξπ using heavy-baryon chiral perturbation theory to quantify the |ΔI| = 1/2 rule in these decay modes. The ratio of |ΔI| = 3/2 to |ΔI\ = 1/2 amplitudes is somewhat larger in these decays than it is in other hyperon decays. At leading order there are two operators responsible for the |ΔI| = 3/2 parts of the Ω- decays which also contribute at one loop to other hyperon decays. These one-loop contributions are sufficiently large to indicate (albeit not definitely) that the measured ratio Γ(Ω- → Ξ0π-)/Γ(Ω- → Ξ-π0) ≈ 2.7 may be too large.
|Number of pages||7|
|Journal||Physics Letters B|
|Publication status||Published - 1999|