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Measurements of the rare decays B -> Kl+l- and B -> K*l+l-

The BABAR Collaboration·B. Aubert
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Abstract

We present measurements of the flavor-changing neutral current decays B -> Kl+l- and B -> K*l+l-, where l+l- is either an e+e- or mu+mu- pair. The data sample comprises 229 X 10^6 Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II e+e- storage ring. We measure the branching fractions BF(B -> Kl+l-) = (0.34 +- 0.07 +- 0.03) X 10^-6 and BF(B -> K*l+l-) = (0.78^{+0.19}_{-0.17} +/- 0.12) X 10^-6, the direct CP asymmetries of these decays, and the relative abundances of decays to electrons and muons.

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The BABAR Collaboration, B. Aubert. 2005-07-01. Measurements of the rare decays B -> Kl+l- and B -> K*l+l-. https://arxiv.org/abs/hep-ex/0507005

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