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arXiv · hep-ph/0207189

Vector-meson contributions do not explain the rate and spectrum in K_L -> pi0 gamma gamma

F. Gabbiani·G. Valencia
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Abstract

We analyze the recent NA48 data for the reaction K_L -> pi0 gamma gamma with and without the assumption of vector meson dominance (VMD). We find that the data is well described by a three-parameter expression inspired by O(p^6) chiral perturbation theory. We also find that it is impossible to fit the shape of the decay distribution and the overall rate simultaneously if one imposes the VMD constraints on the three parameters. We comment on the different fits and their implications for the CP-conserving component of the decay K_L -> pi0 e+ e-.

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F. Gabbiani, G. Valencia. 2002-08-12. Vector-meson contributions do not explain the rate and spectrum in K_L -> pi0 gamma gamma. https://doi.org/10.1103/physrevd.66.074006

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