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K_L -> pi0 gamma gamma and the bound on the CP-conserving K_L -> pi0 e+e-

F. Gabbiani·G. Valencia
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Abstract

It has been known for many years that there is a CP-conserving component for the decay mode K_L -> pi0 e+e- and that its magnitude can be obtained from a measurement of the amplitudes in the K_L -> pi0 gamma gamma decay mode. We point out that the usual description of the latter in terms of a single parameter, a_V, is not sufficient to extract the former in a model independent manner. We further show that there exist known physics contributions to K_L -> pi0 gamma gamma that cannot be described in terms of the single parameter a_V. We conclude that a model independent analysis requires the experimental extraction of three parameters.

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F. Gabbiani, G. Valencia. 2001-08-01. K_L -> pi0 gamma gamma and the bound on the CP-conserving K_L -> pi0 e+e-. https://doi.org/10.1103/physrevd.64.094008

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