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Search for B^+ --> K^+l^+l^- and B^0 --> K^(*0)l^+l^-

The BABAR Collaboration·B. Aubert
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Abstract

Using a sample of 3.7 x 10^{6} Y(4S) --> B-anti-B events collected with the BABAR detector at the PEP-II storage ring, we search for the electroweak penguin decays B^+ --> K^+e^+e^-, B^+ --> K^+mu^+mu^-, B^0 --> K^{*0)e^+e^-, and B^0 --> K^{*0)mu^+mu^-. We observe no significant signals for these modes and set preliminary 90% C.L. upper limits of B(B^+ --> K^+e^+e^-) < 12.5 x 10^{-6}, B(B^+ --> K^+mu^+mu^-) < 8.3 x 10^{-6}, B(B^0 --> K^{*0)e^+e^-) < 24.1 x 10^{-6}, B(B^0 --> K^{*0)mu^+mu^-) < 24.5 x 10^{-6}.

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The BABAR Collaboration, B. Aubert. 2000-08-23. Search for B^+ --> K^+l^+l^- and B^0 --> K^(*0)l^+l^-. https://arxiv.org/abs/hep-ex/0008059

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