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Studying the scale and q^2 dependence of K^+-->pi^+e^+e^- decay

H. Burkhardt·J. Lowe·G. Eilam·M. D. Scadron
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Abstract

We extract the K^+-->pi^+e^+e^- amplitude scale at q^2=0 from the recent Brookhaven E865 high-statistics data. We find that the q^2=0 scale is fitted in excellent agreement with the theoretical long-distance amplitude. Lastly, we find that the observed q^2 shape is explained by the combined effect of the pion and kaon form-factor vector-meson-dominance rho, omega and phi poles, and a charged pion loop coupled to a virtual photon-->e^+e^- transition.

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H. Burkhardt, J. Lowe, G. Eilam, M. D. Scadron. 2000-11-28. Studying the scale and q^2 dependence of K^+-->pi^+e^+e^- decay. https://doi.org/10.1016/s0370-2693(01)00656-6

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