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arXiv · hep-ex/0411069

Measurement of the Radiative Ke3 Branching Ratio

NA48 collaboration
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Abstract

We present a measurement of the relative branching ratio of the decay KL -> pi e nu gamma (Ke3gamma) with respect to KL-> pi e nu (gamma) (Ke3+Ke3gamma) decay. The result is based on observation of 19 000 Ke3gamma and 5.6 x 10^6 Ke3 decays. The value of the branching ratio is Br(Ke3gamma, Egamma^*>30 MeV,theta(e,gamma)^*>20^o)/Br(Ke3)= (0.964+-0.008+0.011-0.009)%. This result agrees with theoretical predictions but is at variance with a recently published result.

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NA48 collaboration. 2004-11-29. Measurement of the Radiative Ke3 Branching Ratio. https://doi.org/10.1016/j.physletb.2004.11.056

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