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Search for the decay K+ to pi+ gamma gamma in the pi+ momentum region P>213 MeV/c

E949 Collaboration·A. V. Artamonov
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Abstract

We have searched for the K+ to pi+ gamma gamma decay in the kinematic region with pi+ momentum close to the end point. No events were observed, and the 90% confidence-level upper limit on the partial branching ratio was obtained, B(K+ to pi+ gamma gamma, P>213 MeV/c) < 8.3 x 10-9 under the assumption of chiral perturbation theory including next-to-leading order ``unitarity'' corrections. The same data were used to determine an upper limit on the K+ to pi+ gamma branching ratio of 2.3 x 10-9 at the 90% confidence level.

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E949 Collaboration, A. V. Artamonov. 2005-07-26. Search for the decay K+ to pi+ gamma gamma in the pi+ momentum region P>213 MeV/c. https://doi.org/10.1016/j.physletb.2005.07.057

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