Weak low-energy couplings from topological zero-mode wavefunctions

Hernandez, P.; Laine, M.; Pena, C.; Torro, E.; Wennekers, J.; Wittig, H.

Weak low-energy couplings from topological zero-mode wavefunctions

Authors

Description

We discuss a new method to determine the low-energy couplings of the $ΔS=1$ weak Hamiltonian in the $ε$-regime. It relies on a matching of the topological poles in $1/m^2$ of three-point functions of two pseudoscalar densities and a four-fermion operator computed in lattice QCD, to the same observables in the Chiral Effective Theory. We present the results of a NLO computation in chiral perturbation theory of these correlation functions together with some preliminary numerical results.
7 pages. Contribution to Lattice 2007