Determination of the $\Delta S=1$ weak Hamiltonian in the SU(4) chiral limit through topological zero-mode wave functions

Abstract

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 $\epsilon$-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.

arXiv comment38 pages, 9 figures

References in corpus (32)

• Exactly massless quarks on the lattice
• A Method for Simulating Chiral Fermions on the Lattice
• Exact chiral symmetry on the lattice and the Ginsparg-Wilson relation
• Chiral Fermions from Lattice Boundaries
• A construction of lattice chiral gauge theories
• More about exactly massless quarks on the lattice
• Axial symmetries in lattice QCD with Kaplan fermions
• The index theorem in QCD with a finite cut-off
• Chiral Determinant as an Overlap of Two Vacua
• Chiral Perturbation Theory for the Quenched Approximation of QCD
• Quenched Chiral Logarithms
• Vector like gauge theories with almost massless fermions on the lattice
• Lattice QCD without tuning, mixing and current renormalization
• Topological susceptibility in the SU(3) gauge theory
• Numerical techniques for lattice QCD in the $\epsilon$--regime
• Low-energy couplings of QCD from current correlators near the chiral limit
• Lattice QCD in the epsilon-regime and random matrix theory
• Partially Quenched Chiral Perturbation Theory and the Replica Method
• Improving meson two-point functions in lattice QCD
• Deflation acceleration of lattice QCD simulations
• Precision study of the SU(3) topological susceptibility in the continuum
• Low-energy couplings of QCD from topological zero-mode wave functions
• Topological susceptibility from the overlap
• On the renormalized scalar density in quenched QCD
• Low energy effective action of domain-wall fermion and the Ginsparg-Wilson relation
• Overlap Hypercube Fermions in QCD Simulations Near the Chiral Limit
• A strategy to study the role of the charm quark in explaining the Delta{I}=1/2 rule
• K-->pipi amplitudes from lattice QCD with a light charm quark
• Non-perturbative renormalisation of left-left four-fermion operators with Neuberger fermions
• Probing the chiral weak Hamiltonian at finite volumes
• Charm mass dependence of the weak Hamiltonian in chiral perturbation theory
• Progress in kaon physics on the lattice

Cited by in corpus (6)

• Probing the chiral regime of Nf=2 QCD with mixed actions
• Finite Volume Scaling of Pseudo Nambu-Goldstone Bosons in QCD
• Computation of the electromagnetic pion form factor from lattice QCD in the epsilon regime
• Variance reduction with practical all-to-all lattice propagators
• Exploring the role of the charm quark in the $\Delta I=1/2$ rule
• Extracting the electro-magnetic pion form factor from QCD in a finite volume