10.1088/1126-6708/2008/05/043
Hernandez, P.
P.
Hernandez
Laine, Mikko
Mikko
Laine0000-0002-2680-4213
Pena, C.
C.
Pena
Torro, E.
E.
Torro
Wennekers, J.
J.
Wennekers
Wittig, H.
H.
Wittig
Determination of the Delta S=1 weak Hamiltonian in the SU(4) chiral limit through topological zero-mode wave functions
2008
2010-04-26T09:43:59Z
2018-07-24T12:58:23Z
journal_article
https://pub.uni-bielefeld.de/record/1587375
https://pub.uni-bielefeld.de/record/1587375.json
A new method to determine the low-energy couplings of the Delta S = 1 weak Hamiltonian is presented. It relies on a matching of the topological poles in 1/m(2) of three-point correlators of two pseudoscalar densities and a four-fermion operator, measured in lattice QCD, to the same observables computed in the is an element of-regime of chiral perturbation theory. We test this method in a theory with a light charm quark, i.e. with an SU(4) flavour symmetry. Quenched numerical measurements are performed in a 2 fm box, and chiral perturbation theory predictions are worked out up to next-to-leading order. The matching of the two sides allows to determine the weak low-energy couplings in the SU( 4) limit. We compare the results with a previous determination, based on three-point correlators containing two left-handed currents, and discuss the merits and drawbacks of the two procedures.