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arXiv · hep-lat/9707009

New lattice approaches to the $ΔI=1/2$ rule

C. Dawson·G. Martinelli·G. C. Rossi·C. T. Sachrajda·S. Sharpe·M. Talevi·M. Testa
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Abstract

Lattice QCD should allow a derivation of the $ΔI=1/2$ rule from first principles, but numerical calculations to date have been plagued by a variety of problems. After a brief review of these problems, we present several new methods for calculating $K\toππ$ amplitudes. These are designed for Wilson fermions, though they can be used also with staggered fermions. They all involve a non-perturbative determination of matching coefficients. We show how problems of operator mixing can be greatly reduced by using point-split hadronic currents, and how CP violating parts of the $K\toππ$ amplitudes can be calculated by introducing a fake top quark. Many of the methods can also be applied to the calculation of two body non-leptonic B-meson decays.

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C. Dawson, G. Martinelli, G. C. Rossi, C. T. Sachrajda, S. Sharpe, M. Talevi, M. Testa. 1997-07-11. New lattice approaches to the $ΔI=1/2$ rule. https://doi.org/10.1016/s0550-3213(97)00756-6

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