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arXiv · 0710.3993

A Study of the Radiative Ke3 Decay and Search for Direct Photon Emission with the KLOE Detector

Kloe Collaboration
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Abstract

We present a measurement of the ratio R = Γ(\keg;\Estar>30\mev,\qstar>20^\circ)$/$Γ(\kegf)$ and a first measurement of the direct emission contribution in KL semileptonic decays. The measurement is done at the DAFNE phi-factory selecting phi->KL KS decays with the KLOE detector. We use 328 pb^{-1}$ of data corresponding to about 3.5 million Ke3(g) events and about 9000 radiative events. Our result is R=(924 +/- 23(stat) +/-16(syst)10^{-5} for the branching ratio and X=-2.3 +/- 1.3(stat) +/- 1.4(syst) for the parameter describing direct emission.

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Kloe Collaboration. 2008-05-07. A Study of the Radiative Ke3 Decay and Search for Direct Photon Emission with the KLOE Detector. https://doi.org/10.1140/epjc%2Fs10052-008-0634-2

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