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Measurement of the Branching Ratio and Form Factors for the Decay \boldmath $K_L\toπ^{\pm}π^0e^{\mp}ν_e(\barν_e)

NA48 Collaboration·J. R. Batley
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Abstract

The $K_L\toπ^{\pm}π^0e^{\mp}ν_e(\barν_e)$ decay was investigated with the NA48 detector at CERN SPS using a beam of long-lived neutral kaons. The branching ratio $Br(K_L\toπ^{\pm}π^0e^{\mp}ν_e(\barν_e))=(5.21\pm 0.07_{stat}\pm 0.09_{syst})\times 10^{-5}$ was fixed from a sample of 5464 events with 62 background events. The form factors $\bar{f}_s$, $\bar{f}_p$, $λ_g$ and $\bar{h}$ were found to be in agreement with previous measurements but with higher accuracy. The coupling parameter of the chiral Lagrangian $L_3=(-4.1\pm 0.2)\times 10^{-3}$ was evaluated from the data.

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NA48 Collaboration, J. R. Batley. 2004-05-07. Measurement of the Branching Ratio and Form Factors for the Decay \boldmath $K_L\toπ^{\pm}π^0e^{\mp}ν_e(\barν_e). https://doi.org/10.1016/j.physletb.2004.05.026

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