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Long distance contribution to $K^+ \to π^+ ν{\bar ν}$ decay and $O(p^4)$ terms in CHPT

S. Fajfer
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Abstract

The long distance contribution to $K^+ \to π^+ ν{\bar ν} $ is calculated using chiral perturbation theory. The leading contribution comes from $O(p^4)$ tree terms. The branching ratio of the $O(p^4)$ long distance contribution is found to be of order $10_{-3}$ smaller than the short distance contributions.

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S. Fajfer. 1996-02-15. Long distance contribution to $K^+ \to π^+ ν{\bar ν}$ decay and $O(p^4)$ terms in CHPT. https://doi.org/10.1007/bf03035889

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