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A measurement of the branching fraction of the exclusive decay B^0 --> K^{*0}gamma

The BABAR Collaboration·B. Aubert
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Abstract

The b --> s gamma transition proceeds by a loop ``penguin'' diagram. It may be used to measure precisely the couplings of the top quark and to search for the effects of any new particles appearing in the loop. We present a preliminary measurement of the branching fraction of the exclusive decay, B^0 --> K^{*0}gamma. We use 8.6 x 10^6 B-anti-B decays to measure B(B^0 --> K^{*0}gamma) = (5.4+/-0.8+/-0.5) x 10^{-5}.

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The BABAR Collaboration, B. Aubert. 2000-08-23. A measurement of the branching fraction of the exclusive decay B^0 --> K^{*0}gamma. https://arxiv.org/abs/hep-ex/0008055

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