Measurement of the radiative Ke3 branching ratio

We present a measurement of the relative branching ratio of the decay K0→π±e±νγ(Ke3γ) with respect to K0→π±e±ν(Ke3+Ke3γ) decay. The result is based on observation of 19 000 Ke3γ and 5.6×106Ke3 decays. The value of the branching ratio is Br(Ke3γ0,Eγ*>30MeV, θeγ*>20°)/Br(Ke30)=(0.964±0.008−0.009+0.011)%. This result agrees with theoretical predictions but is at variance with a recently published result.