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Analysis of the DeltaI=1/2 Rule and e'/e with Overlap Fermions

S. Capitani·L. Giusti
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Abstract

We study the renormalization of the DeltaS=1 effective weak Hamiltonian with overlap fermions. The mixing coefficients among dimension-six operators are computed at one loop in perturbation theory. As a consequence of the chiral symmetry at finite lattice spacing and of the GIM mechanism, which turns out to be quadratic in the masses, the K-->pi pi and K -->pi matrix elements relevant for the Delta I =1/2 rule can be computed without any power subtractions. The analogous amplitudes for e'/e require one divergent subtraction only, which can be performed non-perturbatively using K-->0 matrix elements.

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S. Capitani, L. Giusti. 2001-04-04. Analysis of the DeltaI=1/2 Rule and e'/e with Overlap Fermions. https://doi.org/10.1103/physrevd.64.014506

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