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arXiv · 0804.0896

Evidence for CP violation in B0->J/Psi pi0 decays

B. Aubert
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Abstract

We present measurements of the branching fraction and time-dependent CP asymmetries in B0->J/Psi pi0 decays based on 466 million Y(4S)->BBbar events collected with the BaBar detector at the SLAC PEP-II asymmetric-energy B factory. We measure the CP asymmetry parameters S=-1.23 +/- 0.21 +/- 0.04 and C=-0.20 +/- 0.19 +/- 0.03, where the measured value of S is 4.0 standard deviations from zero including systematic uncertainties. The branching fraction is determined to be B(B0->J/Psi pi0)=(1.69 +/- 0.14 +/- 0.07)*10^{-5}.

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B. Aubert. 2008-04-06. Evidence for CP violation in B0->J/Psi pi0 decays. https://doi.org/10.1103/physrevlett.101.021801

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