Measurements of the rare decay K_{L} -> e^{+} e^{-} e^{+} e^{-}

The KTeV Collaboration; A. Alavi-Harati

doi:10.1103/physrevlett.86.5425

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arXiv · hep-ex/0104043

Measurements of the rare decay K_{L} -> e^{+} e^{-} e^{+} e^{-}

The KTeV Collaboration·A. Alavi-Harati

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Abstract

We observe 441 K_{L} -> e^{+} e^{-} e^{+} e^{-} candidate events with a background of 4.2 events and measure B(K_{L} -> e^{+} e^{-} e^{+} e^{-}) = (3.72 \pm 0.18(stat) \pm 0.23(syst)) \times 10^{-8} in the KTeV/E799II experiment at Fermilab. Using the distribution of the angle between the planes of the e^{+} e^{-} pairs, we measure the CP parameters beta_{CP} = -0.23 \pm 0.09(stat) \pm 0.02(syst) and gamma_{CP} = -0.09 \pm 0.09(stat) \pm 0.02(syst). We also present the first detailed study of the e^{+} e^{-} invariant mass spectrum in this decay mode.

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The KTeV Collaboration, A. Alavi-Harati. 2001-04-24. Measurements of the rare decay K_{L} -> e^{+} e^{-} e^{+} e^{-}. https://doi.org/10.1103/physrevlett.86.5425

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