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arXiv · hep-ex/0702010

Measurement of CP Asymmetry in B0 to Ks pi0 pi0 Decays

The BABAR Collaboration·B. Aubert
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Abstract

We present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state Ks pi0 pi0, with Ks -> pi+ pi-. We use a sample of approximately 227 million B-meson pairs recorded at the Upsilon(4S) resonance with the BABAR detector at the PEP-II B-Factory at SLAC. From an unbinned maximum likelihood fit we extract the mixing-induced CP-violation parameter S = 0.72 +/- 0.71 +/- 0.08 and the direct CP-violation parameter C = 0.23 +/- 0.52 +/- 0.13, where the first uncertainty is statistical and the second systematic.

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The BABAR Collaboration, B. Aubert. 2007-02-05. Measurement of CP Asymmetry in B0 to Ks pi0 pi0 Decays. https://doi.org/10.1103/physrevd.76.071101

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