6533b7d9fe1ef96bd126be0d

RESEARCH PRODUCT

Strong enhancement of epsilon '/epsilon through final state interactions

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description

We quantify the important effect of strong final state interactions in the weak $K\to2\pi$ amplitudes, using the measured $\pi$--$\pi$ phase shifts with J=0 and $I=0,2$. The final rescattering of the two pions provides a strong enhancement of the $\Delta I =1/2$ amplitude, which so far has been neglected in the theoretical predictions of $\epsilon'/\epsilon$. This correction increases the Standard Model prediction of $\epsilon'/\epsilon$ to values in good agreement with the experimental measurements.