Lattice QCD calculation of the electroweak box diagrams for the kaon semileptonic decays

TL;DR

This paper uses lattice QCD to calculate electroweak box diagrams in kaon semileptonic decays, improving the precision of low energy constants and confirming previous models with reduced uncertainties.

Contribution

It introduces a novel lattice QCD method linking electroweak corrections to chiral perturbation theory, enhancing the accuracy of low energy constants for kaon decays.

Findings

Confirmed previous low energy constants with reduced uncertainties

Validated the minimal resonance model for electroweak corrections

Provided first-principles calculations for axial γW-box diagrams

Abstract

We present a lattice QCD calculation of the axial $\gamma W$-box diagrams relevant for the kaon semileptonic decays. We utilize a recently proposed method, which connects the electroweak radiative corrections in Sirlin's representation to that in chiral perturbation theory. It allows us to use the axial $\gamma W$-box correction in the SU(3) limit to obtain the low energy constants for chiral perturbation theory. From first principles our results confirm the previously used low energy constants provided by the minimal resonance model with a significant reduction in uncertainties.