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arXiv · 0911.1988

Search for the B+ -> K+vv Decay Using Semi-Leptonic Tags

The BABAR Collaboration·B. Aubert
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Abstract

We present an update of the search for the flavor-changing neutral current B+ -> K+vv decay using 351 x 10^6 BB pairs collected at the Y(4S) resonance with the BABAR detector at the SLAC PEP-II B factory. Due to the presence of two neutrinos in the final state, we require the reconstruction of the companion B in the event through the decay channel B- -> D0l-v. We find 38 candidates in the data with an expected background of 31 +/- 12. This allows us to set an upper limit on the branching fraction for B+ -> K+vv of 4.5 x 10^-5 at 90% confidence level.

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The BABAR Collaboration, B. Aubert. 2009-11-12. Search for the B+ -> K+vv Decay Using Semi-Leptonic Tags. https://arxiv.org/abs/0911.1988

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