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arXiv · hep-ph/9801298

Long-distance contributions to the K_L --> mu+ mu- decay width

D. Gomez Dumm·A. Pich
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Abstract

The dispersive two-photon contribution to the K_L --> mu+ mu- decay amplitude is analyzed, using chiral perturbation theory techniques and large-N_C considerations. A consistent description of the decays Pi^0 --> e+ e-, Eta --> mu+ mu- and K_L --> mu+ mu- is obtained. As a byproduct, one predicts Br(Eta --> e+ e-) = (5.8+-0.2) x 10^-9 and Br(K_L --> e+ e-) = (9.0+-0.4) x 10^-12.

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D. Gomez Dumm, A. Pich. 1998-04-21. Long-distance contributions to the K_L --> mu+ mu- decay width. https://doi.org/10.1103/physrevlett.80.4633

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