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arXiv · hep-ex/0412038

Search for CP Violation in Charged-Xi and Lambda Hyperon Decays

HyperCP Collaboration·T. Holmstrom·N. Leros·R. A. Burnstein·A. Chakravorty·A. Chan·Y. C. Chen·W. S. Choong·K. Clark·E. C. Dukes·C. Durandet·J. Felix·Y. Fu·G. Gidal·P. Gu·H. R. Gustafson·C. Ho·M. Huang·C. James·C. M. Jenkins·T. Jones·D. M. Kaplan·L. M. Lederman·M. J. Longo·F. Lopez·L. C. Lu·W. Luebke·K. B. Luk·K. S. Nelson·H. K. Park·J. P. Perroud·D. Rajaram·H. A. Rubin·P. K. Teng·J. Volk·C. G. White·S. L. White·P. Zyla
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Abstract

We have compared the proton and antiproton angular distributions in 117 million Xi-minus -> Lambda + pi-minus -> proton + pi-minus + pi-minus and 41 million anti-Xi-minus -> anti-Lamba + pi-plus -> antiproton + pi-plus + pi-plus decays using a subset of the data from the HyperCP experiment (E871) at Fermilab. We find no evidence of CP violation, with the direct-CP-violating parameter $A_{ΞΛ} = \frac{α_Ξα_Λ - \barα_Ξ\barα_Λ}{α_Ξα_Λ + \barα_Ξ\barα_Λ} = [0.0+/-5.1(stat)+/-4.4(syst)]{\times}10^{-4}$.

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HyperCP Collaboration, T. Holmstrom, N. Leros, R. A. Burnstein, A. Chakravorty, A. Chan, Y. C. Chen, W. S. Choong, K. Clark, E. C. Dukes, C. Durandet, J. Felix, Y. Fu, G. Gidal, P. Gu, H. R. Gustafson, C. Ho, M. Huang, C. James, C. M. Jenkins, T. Jones, D. M. Kaplan, L. M. Lederman, M. J. Longo, F. Lopez, L. C. Lu, W. Luebke, K. B. Luk, K. S. Nelson, H. K. Park, J. P. Perroud, D. Rajaram, H. A. Rubin, P. K. Teng, J. Volk, C. G. White, S. L. White, P. Zyla. 2004-12-13. Search for CP Violation in Charged-Xi and Lambda Hyperon Decays. https://doi.org/10.1103/physrevlett.93.262001

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