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Time-Dependent CP-Violating Asymmetries in b -> s qbar q Transitions

The Belle Collaboration·K. -F. Chen
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Abstract

We present new measurements of CP-violation parameters in B0 -> phiK0, K+K-Ks, f0(980)Ks, eta'Ks, omegaKs and Kspi0 decays based on a sample of 275 x 10^6 BBbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. One neutral B meson is fully reconstructed in one of the specified decay channels, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters for each of the decay modes are obtained from the asymmetries in the distributions of the proper-time intervals between the two B decays. The combined result for the B0->phiK0, K+K-Ks, f0(980)Ks, eta'Ks, omegaKs, Kspi0, and previously reported KsKsKs decays differs from the SM expectation by 2.4 standard deviations.

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The Belle Collaboration, K. -F. Chen. 2005-07-15. Time-Dependent CP-Violating Asymmetries in b -> s qbar q Transitions. https://doi.org/10.1103/physrevd.72.012004

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