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arXiv · 0707.4634

A Study of the Radiative KL->pi nu e (g) Decay and Possible Osservation of Direct Photon Emission with the KLOE Detector

Kloe Collaboration
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Abstract

We present the measurement of the ratio R = \frac{Γ(\keg;\Estar>30\mev,\qstar>20^\circ)}{Γ(\kegf)} and a first measurement of the direct emission contribution for the same process. We use 328 pb^{-1} of data collected at \kloe in 2001 and 2002, corresponding to about 3 million of \kegf events and about 9 thousand \keg radiative events. Our result is R= (924 \pm 23_{stat} \pm 16_{syst})10^{-5} for the branching ratio and X =-2.3\pm 1.3_{stat}\pm 1.4_{syst} for the parameter describing direct emission.

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Kloe Collaboration. 2007-07-31. A Study of the Radiative KL->pi nu e (g) Decay and Possible Osservation of Direct Photon Emission with the KLOE Detector. https://arxiv.org/abs/0707.4634

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