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Measurement of CP Asymmetries in B0-> KS pi0 pi0 Decays

B. Aubert·BABAR Collaboration
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Abstract

We present a preliminary 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- and pi0-> gamma gamma. We use a sample of approximately 227 million B-meson pairs recorded at the Y(4S) resonance by the BaBar detector at the PEP-II B-Factory at SLAC. From a maximum likelihood fit we extract the mixing-induced CP-violation parameter S = 0.84 +/- 0.71(stat} +/- 0.08{syst) and the direct CP-violation parameter C = 0.27 +/- 0.52(stat) +/- 0.13(syst}, where the first uncertainty is statistical and the second systematic.

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B. Aubert, BABAR Collaboration. 2005-08-07. Measurement of CP Asymmetries in B0-> KS pi0 pi0 Decays. https://arxiv.org/abs/hep-ex/0508017

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