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Observation of CP violation in B^0 -> eta' K^0 Decays

The BABAR Collaboration·B. Aubert
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Abstract

We present measurements of the time-dependent CP-violation parameters S and C in B^0 --> eta' K^0 decays. The data sample corresponds to 384 million B Bar pairs produced by e^+ e^- annihilation at the Y(4S). The results are S = 0.58 +- 0.10 +- 0.03 and C = -0.16 +- 0.07 +- 0.03. We observe mixing-induced CP violation with a significance of 5.5 standard deviations in this b -> s penguin dominated mode.

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The BABAR Collaboration, B. Aubert. 2007-03-16. Observation of CP violation in B^0 -> eta' K^0 Decays. https://doi.org/10.1103/physrevlett.98.031801

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