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Lattice calculation of matrix elements relevant for Delta I=1/2 rule and epsilon-prime

D. Pekurovsky·G. Kilcup
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Abstract

We have gained enough statistical precision to distinguish signal from noise in matrix elements of all operators relevant for the Delta I=1/2 rule in kaon decays and for the direct CP violation parameter epsilon-prime. We confirm significant enhancement of Delta I=1/2 transitions observed in experiments, although a few large systematic uncertainties remain in our predictions: higher-order chiral corrections and lattice spacing dependence. The estimate of epsilon-prime parameter is further complicated by the problem of matching lattice and continuum operators.

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D. Pekurovsky, G. Kilcup. 1999-03-15. Lattice calculation of matrix elements relevant for Delta I=1/2 rule and epsilon-prime. https://arxiv.org/abs/hep-lat/9903025

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