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Observation of Parity Violation in the Omega-minus -> Lambda + K-minus Decay

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

The alpha decay parameter in the process Omega-minus -> Lambda + K-minus has been measured from a sample of 4.50 million unpolarized Omega-minus decays recorded by the HyperCP (E871) experiment at Fermilab and found to be [1.78 +/- 0.19(stat) +/- 0.16(syst)]{\times}10^{-2}. This is the first unambiguous evidence for a nonzero alpha decay parameter, and hence parity violation, in the Omega-minus -> Lambda + K-minus decay.

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HyperCP Collaboration, L. C. Lu, R. A. Burnstein, A. Chakravorty, Y. C. Chen, W. -S. Choong, K. Clark, E. C. Dukes, C. Durandet, J. Felix, Y. Fu, G. Gidal, H. R. Gustafson, T. Holmstrom, M. Huang, C. James, C. M. Jenkins, T. D. Jones, D. M. Kaplan, M. J. Longo, W. Luebke, K. -B. Luk, K. S. Nelson, H. K. Park, J. -P. Perroud, D. Rajaram, H. A. Rubin, J. Volk, C. G. White, S. L. White, P. Zyla. 2005-05-06. Observation of Parity Violation in the Omega-minus -> Lambda + K-minus Decay. https://doi.org/10.1016/j.physletb.2005.04.067

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