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Search for the rare decay K+ -> pi+ gamma

E787 Collaboration
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Abstract

We have performed a search for the angular-momentum forbidden decay K+ -> pi+ gamma with the E787 detector at BNL. No events were observed in the pi+ kinematic region around 227 MeV/c. An upper limit on the branching ratio for the decay is determined to be 3.6 x 10^{-7} at 90% confidence level.

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E787 Collaboration. 2001-12-11. Search for the rare decay K+ -> pi+ gamma. https://doi.org/10.1103/physrevd.65.052009

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