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arXiv · hep-ph/9810523

Short- and long-distance contributions to the rare decay K_L-->mu+ mu-

D. Gomez Dumm·A. Pich
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Abstract

The interplay between short- and long-distance contributions to the K_L-->mu+ mu- decay amplitude is analyzed. The long-distance piece is estimated using chiral perturbation theory techniques and large-N_C considerations, leading to a consistent description of the pi^0-->e+ e-, eta-->mu+ mu- and K_L-->mu+ mu- branching ratios.

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D. Gomez Dumm, A. Pich. 1998-10-29. Short- and long-distance contributions to the rare decay K_L-->mu+ mu-. https://doi.org/10.1016/s0920-5632(99)00159-0

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