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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 new measurement of the branching ratio of the decay K_L -> pi e nu gamma (Ke3g) with respect to K_L -> pi e nu (Ke3), and the first study of the photon energy spectrum in this decay. We find BR(Ke3g, E*g>30 MeV, theta*_eg>20 deg)/BR(Ke3) = 0.908 +- 0.008 (stat.) +0.013-0.012 (syst.). Our measurement of the spectrum is consistent with inner bremsstrahlung as the only source of photons in Ke3g.

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Douglas R. Bergman. 2001-06-14. A New Measurement of the Radiative Ke3 Branching Ratio and Photon Spectrum. https://doi.org/10.1103/physrevd.64.112004

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