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تسجيل مستخدم جديدIsospin Breaking in $K_{ell 4}$ Decays of the Neutral Kaon
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A. Nehme
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In the presence of photons, the neutral $K_{ell 4}$ decay, $K^0topi^0pi^-ell^+ u_ell$, can be parameterized in terms of three vectorial, one anomalous, and one tensorial form factors. We present here analytic expressions of two vectorial form factors, $f$ and $g$, calculated at one-loop level in the framework of chiral perturbation theory based on the effective Lagrangian including mesons, photons, and leptons. These expressions may then be used to disentangle the Isospin breaking part from the measured form factors and hence improve the accuracy in the determination of $pipi$ scattering parameters from $K_{ell 4}$ experiments.
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The charged $K_{ell 4}$ decay, $K^+topi^+pi^-ell^+ u_{ell}$ is studied in the framework of chiral perturbation theory based on the effective Lagrangian including mesons, photons, and leptons. We give analytic expressions for the two vectorial form fa
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