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Estimates of $ε\prime/ε$

M. Ciuchini·E. Franco·G. Martinelli·L. Reina
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Abstract

We review the latest calculations of the next-to-leading $\DSone$ effective Hamiltonian, relevant for $K\to ππ$ transitions. Numerical results for the Wilson coefficients are given for different regularization schemes. Predictions of $\epse$, obtained using different approaches to evaluate the relevant hadronic matrix elements, are compared. Given the present value of the top mass, $m_t=(174\pm 17)$ GeV, all the analyses, in spite of the large theoretical uncertainties, indicate that the value of $\epse$ is smaller than $1\times 10^{-3}$.

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M. Ciuchini, E. Franco, G. Martinelli, L. Reina. 1995-03-10. Estimates of $ε\prime/ε$. https://arxiv.org/abs/hep-ph/9503277

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