A framework for exploring the interactions and decays of hyperons with lattice QCD

In this work we outline a program for lattice QCD that would greatly contribute to understanding the strong and weak interactions of strange baryons. The low-energy effective field theory describing hyperon-nucleon scattering in QCD and partially-quenched QCD is constructed. This framework will allow lattice simulations of the low-energy scattering parameters to be extrapolated to the physical values of the quark masses. We explore the long-standing discrepancies in the P-wave amplitudes for non-leptonic hyperon decays using two-flavor chiral perturbation theory, and emphasize that the problem is not merely an artifact of perturbing about the chiral limit of the three-flavour theory. As energy is not conserved in the lattice simulation of the Λ→N two-point function, we include the surface terms in the effective field theory required to determine the underlying weak amplitude.