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arXiv · hep-ph/9401204

Long Distance Contribution to $K^+ \rightarrow π^+ ν\barν$

Ming Lu·Mark B. Wise
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Abstract

We estimate the long distance contribution to the $K^+ \rightarrow π^+ ν\barν$ decay amplitude using chiral perturbation theory. We find that it is likely to be less than a few percent of the part of the short distance contribution proportional to the square of the charm quark mass. In the large $N_c$ limit the leading (in chiral perturbation theory) long distance contribution to $K^+ \rightarrow π^+ ν\barν$ from Feynman diagrams with a $W$ and $Z^0$ vanishes.

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Ming Lu, Mark B. Wise. 1994-01-03. Long Distance Contribution to $K^+ \rightarrow π^+ ν\barν$. https://doi.org/10.1016/0370-2693(94)90223-2

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