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arXiv · hep-ex/9905022

Observation of $K_S^0$ semileptonic decays with CMD-2 detector

CMD2 Collaboration
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Abstract

The decay $K_S^0 \to πe ν$ has been observed by the CMD-2 detector at the e^+e^- collider VEPP-2M at Novosibirsk. Of 6 million produced $K_L^0K_S^0$ pairs, $75 \pm 13$ events of the $K_S^0 \to πe ν$ decay were selected. The corresponding branching ratio is $B(K_S^0 \to πe ν)=(7.2 \pm 1.4)\times10^{-4}$. This result is consistent with the evaluation of $B(K_S^0 \to πe ν)$ from the $K_L^0$ semileptonic rate and $K_S^0$ lifetime assuming $ΔS=ΔQ$ .

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CMD2 Collaboration. 1999-05-14. Observation of $K_S^0$ semileptonic decays with CMD-2 detector. https://doi.org/10.1016/s0370-2693(99)00443-8

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