Measurement of the radiative $K_{e3}$ branching ratio

We present a measurement of the relative branching ratio of the decay $K^{0} \to \pi^{\pm}e^{\pm}\nu\gamma (K_{e3\gamma})$ with respect to $K^{0} \to \pi^{\pm} e^{\pm}\nu(K_{e3} + K_{e3\gamma})$ decay. The result is based on observation of 19 000 $K_{e3\gamma}$ and $5.6 \times 10^{6} K_{e3}$ decays. The value of branching ratio is Br$(K^{0}_{e3\gamma}, E^{*}_{\gamma}$ > 30 MeV, $\theta^{*}_{e\gamma}$ > $20^{\circ})$ / Br$(K^{0}_{e3}) = (0.964 \pm 0.008^{+0.011}_{0.009})$%. This result agrees with the theoretical predictions but is at variance with a recently published result.