NONLEPTONIC HYPERON DECAYS IN CHIRAL PERTURBATION-THEORY

The non-leptonic hyperon decays are analyzed up to one-loop order incl uding all counterterms in the framework of heavy baryon chiral perturb ation theory. We use the exchange of the spin-3/2 decuplet resonances as an indication of which low-energy constants contribute significantl y to these investigated processes. We choose four independent decay am plitudes that are not related by isospin relations in order to perform a fit for the pertinent low-energy constants and find a satisfactory fit both for s- and p-waves. The chiral corrections to the lowest orde r forms for the s-waves are moderate whereas there are significant mod ifications of the p-wave amplitudes.