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arXiv · hep-ph/9207233

The Rare Decays $\piee$, $\etaee$ and \etamumu$ in Chiral Perturbation Theory

Martin J. Savage·Michael Luke·Mark B. Wise
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Abstract

We calculate the decay rates for $\piee$, $\etaee$ and $\etamumu$ in chiral perturbation theory. The linear combination of counterterms necessary to render these amplitudes finite is fixed by the recently measured branching fraction for $\etamumu$. We find $\Br(\piee ) = 7\pm 1\times 10^{-8}$ and $\Br(\etaee )=5\pm 1\times 10^{-9}$.

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Martin J. Savage, Michael Luke, Mark B. Wise. 1992-07-10. The Rare Decays $\piee$, $\etaee$ and \etamumu$ in Chiral Perturbation Theory. https://doi.org/10.1016/0370-2693(92)91407-z

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