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arXiv · 0901.1223

Evidence for B+ -> K*0bar K*+

The BABAR Collaboration·B. Aubert
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Abstract

We present measurements of the branching fraction and fraction of longitudinal polarization for the decay B+ -> K*0bar K*+ with a sample of 467 +/- 5 million BBbar pairs collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at the SLAC National Accelerator Laboratory. We obtain the branching fraction Br(B+ -> K*0bar K*+) = (1.2 +/- 0.5 +/- 0.1) x 10^{-6} with a significance of 3.7 standard deviations including systematic uncertainties. We measure the fraction of longitudinal polarization f_L = 0.75+0.16-0.26 +/- 0.03. The first error quoted is statistical and the second is systematic.

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The BABAR Collaboration, B. Aubert. 2009-01-09. Evidence for B+ -> K*0bar K*+. https://doi.org/10.1103/physrevd.79.051102

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