Final State Interactions and Ε
نویسنده
چکیده
I discuss the rôle of strong final state interactions (FSI) in K → 2π decays. In this case strong FSI effects can be resummed [1,2] by solving the Omnès problem for K → 2π amplitudes. Implications for the CP conserving ∆I = 1/2 ratio and the direct CP violation parameter ε ′ /ε are also discussed.
منابع مشابه
Strong Enhancement of ε/ε Through Final State Interactions
We quantify the important effect of strong final state interactions in the weak K → 2π amplitudes, using the measured π–π phase shifts with J = 0 and I = 0, 2. The final rescattering of the two pions provides a strong enhancement of the ∆I = 1/2 amplitude, which so far has been neglected in the theoretical predictions of ε′/ε. This correction increases the Standard Model prediction of ε′/ε to v...
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Strong final state interaction (FSI) effects can play a central role in the Standard Model prediction of weak K → 2π matrix elements. Here, I discuss how FSI's affect the direct CP violation parameter ε ′ /ε by solving the Omnès problem for the necessary K → 2π amplitudes. The main results of this analysis have been reported in a previous paper 1 and are further discussed in Refs. 2,3. The resu...
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