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arXiv · 0708.0304

Improved measurement of time-dependent CP violation in B0 -> J/Psi pi0 decays

S. E. Lee·K. Miyabayashi
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Abstract

We report improved measurements of time-dependent CP violation parameters for $B^0(\bar{B}^0) \to J/ψπ^0$ decay. This analysis is based on 535 million $B\bar{B}$ pairs accumulated at the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. From the distribution of proper time intervals between the two B decays, we obtain the following CP violation parameters $\mathcal{S}_{J/ψπ^0} = -0.65\pm0.21 (\rm{stat})\pm0.05 (\rm{syst})$ and $\mathcal{A}_{J/ψπ^0} = +0.08\pm0.16 (\rm{stat})\pm0.05 (\rm{syst})$, which are consistent with Standard Model expectations.

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S. E. Lee, K. Miyabayashi. 2007-12-17. Improved measurement of time-dependent CP violation in B0 -> J/Psi pi0 decays. https://doi.org/10.1103/physrevd.77.071101

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