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Measurements of Branching Fractions and Time-Dependent CP-Violating Asymmetries in B to eta' K Decays

the BaBar Collaboration·B. Aubert
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Abstract

We present measurements of the B -> eta' K branching fractions;for B+ -> eta' K+ we measure also the time-integrated charge asymmetry Ach, and for B0 -> eta' K0S the time dependent CP-violation parameters S and C. The data sample corresponds to 232 million B Bbar pairs produced by e+ e- annihilation at the Upsilon(4S). The results are BF(B+ -> eta' K+) = (68.9 +- 2.0 +- 3.2) * 10^-6, BF(B0 -> eta' K0) = (67.4 +- 3.3 +- 3.2) * 10^-6, Ach = 0.033 +- 0.028 +- 0.005, S=0.30 +- 0.14 +- 0.02, C=-0.21 +- 0.10 +- 0.02, where the first error is statistical and the second systematic.

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the BaBar Collaboration, B. Aubert. 2005-02-08. Measurements of Branching Fractions and Time-Dependent CP-Violating Asymmetries in B to eta' K Decays. https://doi.org/10.1103/physrevlett.94.191802

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