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A New Measurement of the Radiative Ke3 Branching Ratio and Photon Spectrum

Douglas R Bergman
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Abstract

We present a preliminary report on a new measurement of the radiative neutral Ke3 branching ratio and the first study of the photon spectrum in this decay. We find BR(Ke3g, E*_g>30 GeV, Th*_eg>20 deg)/BR(Ke3) = 0.911+-0.009(stat)+0.021-0.010(syst)%. Our measurement of the spectrum is consistent with inner bremsstrahlung only as the source of photons at the 2 sigma level.

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Douglas R Bergman. 2000-09-12. A New Measurement of the Radiative Ke3 Branching Ratio and Photon Spectrum. https://arxiv.org/abs/hep-ex/0009032

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