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Measurement of direct photon emission in $K^+ \to π^+ π^0 γ$ decay using stopped positive kaons

Suguru Shimizu·for KEK-E470 Collaboration
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Abstract

The radiative decay $K^+ \to π^+ π^0 γ$ ($K_{π2 γ}$) has been measured with stopped positive kaons. A $K_{π2 γ}$ sample containing 4k events was analyzed, and the $K_{π2 γ}$ branching ratio of the direct photon emission process was determined to be $[6.1\pm2.5({\rm stat})\pm1.9({\rm syst})]\times 10^{-6}$. No interference pattern with internal bremsstrahlung was observed.

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Suguru Shimizu, for KEK-E470 Collaboration. 2002-12-19. Measurement of direct photon emission in $K^+ \to π^+ π^0 γ$ decay using stopped positive kaons. https://doi.org/10.1016/s0370-2693(02)03236-7

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