Measurement of the Radiative Ke3 Branching Ratio

TL;DR

This paper reports a precise measurement of the radiative Ke3 decay branching ratio, comparing experimental data with theoretical predictions and highlighting discrepancies with recent results.

Contribution

The study provides a new, accurate measurement of the Ke3gamma branching ratio, using a large dataset, and compares it with theoretical models and previous experimental findings.

Findings

Measured branching ratio: (0.964+-0.008+0.011-0.009)%

Results agree with theoretical predictions

Results differ from recent published measurements

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.