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arXiv · 1109.1527

Search for CP Violation in the Decay tau- -> pi- K^0_S (>= 0 pi0) nu_tau

The BABAR Collaboration
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Abstract

We report a search for CP violation in the decay τ- -> π- \K^0_S (>= 0 π0) ν_τ using a dataset of 437 million τ lepton pairs, corresponding to an integrated luminosity of 476 fb^{-1}, collected with the BABAR detector at the PEP-II asymmetric energy e+e- storage rings. The CP-violating decay-rate asymmetry is determined to be (-0.45 +/- 0.24 +/- 0.11)%, approximately three standard deviations from the Standard Model prediction of (0.33 +/- 0.01)%.

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The BABAR Collaboration. 2012-01-15. Search for CP Violation in the Decay tau- -> pi- K^0_S (>= 0 pi0) nu_tau. https://doi.org/10.1103/physrevd.85.031102

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